GIS Modeling Email Dialog

   …an introduction to grid-based map analysis and modeling



GEOG 3110, University of Denver, Geography, Winter Term 2011

Thursdays 6:00-9:30 pm, GIS Lab, Room 126, Boettcher (West)



…<click here> to review the Report Writing Tips


Keep in mind that for all the lab exercises you have several “life lines” if you need them—


·         normal open door office hours 3:00 to 5:00 pm Thursdays (or as specially arranged on Fridays), or

·         arrange for an “working meeting” in the GIS Lab on Thursdays between 10:00 am and 3:00 pm Thursdays, or

·         arrange for a phone/Skype call via email for tutorial walk-thru (you need to be at a computer with MapCalc/Surfer), or

·         send me an email with a specific question…


 Send an email with your question(s) and I will respond and then post the response if your question has general class interest.




(3/5/12) Hi Joe,


Our group is having a problem with the scatter plot display in question 8 part 8.  First off we are unsure on why on the bottom of the plot in the equation the y-intersect does not match the picture.

In the attached picture, the equation shows the intersect is 26 and on the plot it does not show there.


We tried with other plots and the line does not line up with the axis.  Also, we would like to know if the plot in MapCalc is not visually accurate or if there is a computer error.  We are unsure what to try next.


Thanks, Paulina and group


Paula, Mining and Sharon—the scatter plot has taken “artistic license” and shifted the vertical/Y axis away from the horizontal/X axis zero point so the plot could be better displayed.  The x-axis should show a break to avoid confusion …but that’s the problem of using a charting package instead of writing your own graphics routine.  Joe






(2/28/12) Hi Dr. Berry-- We are having some confusion on question 4 with respect to the report generated for the map statistics. We did not get a generated report for the subtracted maps, so when you ask for the maximum, minimum and average we are confused as to which report to use. Are we supposed to get a report for the subtracted maps? Thank you, Sharon


Sharon—in the exercise it notes that you need to…


     Be sure to double-click on the difference surface, select the General Tab and click on the “i” button to pop-up the statistics about the map surface—these will be helpful in framing your response to question #4.







(2/23/12) Ken—a student in class asked what the blank/white areas are in the Customer Density Surface slide in the retail competition deck.  Do you recall?  Joe


0 customers, or a ratio less than one.  The values are customers per cell or something - this was a sliced map through the customer profiles.


In Orange County, the white areas are mostly industrial.  This store is in a heavily industrialized area (office space, etc), with mountains and areas where there is no population.  The north-east quadrant is all mountains (Cleveland National Forest). Saddleback Mountain is about 2:00 on the map. 








Graham and Paulina—excellent questions that get at prototype report writing!!!  My responses are embedded below.  Joe


Hi Professor Berry-- Sorry to bother you with so many questions, but Paulina and I were hoping you could clarify some things for our timber harvesting visual exposure project.  Ok, here goes


3. We made a viewshed from houses to harvest blocks map, but we're wondering if we should also make a viewshed from roads to harvest blocks map, and if we should combine those maps.


…that would be an extension to the prototype and something that should be avoided in a prototype report—never unilaterally enlarge the prototype to completely solve the problem.  Rather than implementing the extension you should briefly describe what you recommend in the “Additional Considerations” section of the report.  Keep in mind that a prototype introduces and demonstrates an approach to a client’s solution (often done for free or at very small cost)—it is not the solution.  KISS (keep it simple stupid) is the guiding principle with the prototype stimulating further development of the approach.


4. Would you like us to calibrated and weighted suitability model for the timber harvesting project that we are working on. We've calculated the total and average visual exposure for the houses and the roads to the harvest blocks, and we've also calculated the viewshed from the houses to the harvest blocks, but we're wondering how these five different measures of visual exposure would be useful in our scenario. Basically, we're a little confused about which model would be the most useful in this scenario, or if they should be combined into an overarching suitability model.


…consulting folks would be yelling “mission creep, mission creep!!!” and shutter at unilaterally implementing considerations that are outside the prototype requirements.  Apart the possibility that you could “lose your shirt” by out of scope work solving a problem as a prototype can have a couple of detrimental effects—1) you risk confusing the client by increased complexity of the unilaterally added criteria and 2) could be eating your “seed corn” as a comprehensive prototype can become a tacit solution.    


5. Isn't "Big Guy" supposed to be like Ronald Reagan who only wants a 1-page brief? …no, RR was an outlier with a very busy schedule and limited attention span.  Wouldn't 10 pages and 3000 words be way too much? …most Big Guys want to have some understanding of the critical considerations and proposed approach—but they want a basic understanding in just a few pages without being overwhelmed by technical minutia (that’s Little Guys job).  We noticed on the example project that their introduction basically tells a fictional story. Wouldn't that be too much information for Big Guy and Tech-Guy since they are the ones that hired us and already know the background story. 


…yep, the “background story” is border line and most certainly counter-productive if it drags on.  Generally, the client knows the “story” …in fact that’s why he contacted you for a solution.


Note: I assume questions 1 and 2 below were just for your “enlightenment” and not fodder for an over-the-top “background story” for Big Guy.


1. Who grants harvest blocks to timber companies? The National Forest Service?


…the term “harvest block” is used a lot in Canada (BC and Alberta primarily where clear cutting is primarily used).  The blocks are identified by companies who have leased large tracts of “crown lands” that they manage (radically different from the U.S. where the government manages the land).  In the U.S., the term “timber sale unit” (or parcel) is used more often and the sale units are indentified by the U.S. (or State) Forest Service and bids are submitted by logging companies.  Most of the world’s forest lands follow the Canadian model of “long term leasing” with relatively minimal privately owned timberlands.


2. Do timber companies always harvest entire blocks at a time? Or do they sometimes harvest portions of blocks? 


…from a broad perspective, there are two types of harvesting—clear cuts and selective cuts.  Ecological, engineering and economic considerations primarily determine which type is used.  For selective cutting a portion of the mature trees within a harvesting unit are removed and the understory trees regeneration are left to grow into the gaps.  For this to work the tree species need to be shade “tolerant” (e.g., most hardwood/deciduous trees such as red oak) and are able to survive in the lower levels of sunlight under the remaining tree canopy. 


Clear cutting, on the other hand, is used for species that are shade “intolerant” (e.g., most softwood/conifer trees such as Douglas fir) that thrive in direct sunlight.  Entire blocks are harvested and reseeded or planted much like an agriculture crop except the “rotation” is 50+ years in the west and 20+ years in the southern U.S.  A variant is “seed tree” harvest units where a few mature trees are left to naturally reseed the area.   




(2/7/12) Folks—in grading the Exercise 4 reports I noticed that some of you are ignoring the earlier “helpful tip” that all of the tables should not exceed 6.5 inches in width even though you are preparing and submitting in Web Layout View…


figure tables should fit within normal printer margins (<6.5 inches) or they will be truncated if printed; 8.5” paper width – 1”right margin -1” left margin = 6.5 inches for the body of the report). Even though Web Layout is the primary viewing form, keeping tables to printer limits will work in all computer environments—even smart phone screens. 


You need to pre-plan your table layout keeping in mind that 3 window panes (table cells) is a practical limit to any table that stays within the 6.5 inch limit—four or more panes makes the maps far too small for viewing.  Most web designers center the graphic and the caption both vertically and horizontally within each table cell.  Also they display the table without cell borders visible (or a faint light grey) for easier viewing.


The reason is that tables cannot be “sized on-the-fly” in your browser.  Therefore if a reader resizes the browser window your tables “over hang” the window margins and they have to use the horizontal slider bar to see the right-side of the oversized table.  This doesn’t happen with text as it is automatically pushed to the left as the window variable-width margin is made smaller. 


The use of the “6.5 inch or less” is a default standard that is observed by most programmers and has become the Smart Phone and Tablet standard; and most users that have large screens still view documents in a reduced window that can experience the table “over hang” problem but most will keep their window width to 6.5 inches or more.  Joe




(2/7/12) Hi Joe-- Michael and I are having a discussion about the directions for defining the ranges for the four displays to be compared in Question 1.


I read the directions as a suggestion that we should "force" each of the maps to have both the same number of ranges and the same interval size (i.e. 0 to 5, 5-10, 10-15, etc.) so that cross comparison of the values inhabiting each of the ranges across the displays is possible. The colors in the color ramp would also then represent the same values.


However, Michael reads the directions (and I can appreciate and understand his understanding of the directions as well) a bit differently. He finds that the directions suggest that we use User Defined calculation mode in order to define the number of ranges and range intervals as is appropriate for each display because there are no explicit directions suggesting that we use the same number and interval size for each map. For example, the minimum and maximum slope maps will not contain the same number of ranges as the average and fitted displays and therefore the same number of ranges might not be the same.


Please help us arrive at more clarity on these directions.  Thanks, Alicia


Alicia and Michael—if one is to visually compare maps the legends have to be identical—breakpoints for ranges and corresponding color assignments.


I suggest that you find the Min and Max data value for the entire set of maps, and then use User Defined ranges to construct the best “overall map legend.”  Once constructed, use the Template tab to name and store your legend (Save as…).  Then use the Template tab to recall the legend and apply to each of the maps.


storing   …retrieving


In this manner each map display will have the same “thematic appearance” so a human viewing the set of map displays can “see” the actual differences (not the erroneous differences due to inconsistent colors in the legends).






(2/7/12) Good morning Dr. Berry-- we have a question concerning the slope fitted operation. We noticed that we have negative values when we subtract the 'slope fitted' map from the 'slope max' map, and we can't make sense out of this.  As we understand, the 'slope fitted' value for any given cell should be lower that the slope max for the same cell.


What may be confounding this issue is that we don't completely understand the slope fitted operation and how it differs from the average operation.


Rob, Mike, and Alicia


Rob, Mike, and Alicia—excellent question… the “slope fitted” value being more than the “slope max” value is curious.  One would think this could never happen. 


While this case doesn’t occur very often, it is possible due to the arrangement of the “nine floating balls” with one or more unusual outliers.  Consider the following schematic…



Keep in mind that the “maximum slope” only considers the eight slopes comparing the center cell with its immediate surrounding neighbors.  The “fitted slope” considers all nine surface values at once and an arrangement could occur where two large but opposite slope conditions force the plane to be steeper than the maximum individual slope.


An awesome extension to your report would be to use the Drill-down tool (click on the map display) and note the center and eight surrounding elevation surface values at the location(s) that have the counter intuitive result with “Fitted” greater than “Maximum.”  Calculate the maximum individual slope value (largest of the eight individual rise/run values) then imagine a plane best fitting all nine values—what do you think?






(2/7/12) Folks—if you are still “struggling” with the concepts and calculations behind simple and effective distance, check out…






(2/2/12) Folks—I got it with some meetings but will return your graded Exercise 3 reports this afternoon.  A couple of additional things you ought to consider as you finalize your Exercise 4 reports—


1) A key consideration in boosting a B report to an A is “extended discussion” that goes beyond the explicit confines of the question.  For example…


…good discussion but could have extended the discussion to include what the “at___” and “Orthogonally” options in Clump do.

could have extended the discussion about Size to include calculating the area in square meters (cell-size= 328ft= 100m, therefore each cell is 100*100m= 10,000 sqmeters= 1 hectare; 310 cells= 310 hectares); this might have triggered thinking about the actual ratio (numeric) coupled with choropleth (geographic) data type.


2) Another “grade booster” is insuring that your discussion is clear, concise, and succinct, includes reference to the Shading Manager table, histogram tab and statistics tab when appropriate, and figures are consistently formatted with the SnagIt captures being the same size and centered in both the horizontal and vertical directions in each table “cell.”


Attention to these points will bump your report to high A or A+ realms.  As in life, going beyond basic expectations will carry you far as the mark of a true professional.  Joe




(2/1/12) Folks—I am “plowing” through your Exercise 3 reports.  Michael and Paulina “nailed” the displays in question 3-1a&b.  A quick look at what they did and my comments might be useful to consider as you finalize your Exercise 4 reports.  Joe


1a) Considering the Display Form, Display Type, Mesh on/offData Type and  Shading manager Settings which combination would be most appropriate for displaying the following maps in the Island.rgs database (explain your choices by discussing the geographic and numeric nature of the data)—


Depth map

Figure 1-1: 3D Grid Display of Depth map.


To display the Depth map data, as shown in Fig. 1-1, the most appropriate Display Form/Type is a 3D Grid with the layer mesh on.  This best describes the data type, which is geographically isopleth and ratio quantitative data well stated (see below for a general comment).  The user defined ranges shading manager settings that appeared as the default best represented the data.

…a comprehensive format for reporting a map’s data type is ______________ numeric data type and __________ geographic data type forming a ____________ map surface; for example, Qualitative (Binary) numeric data type and Choropleth geographic data type forming a Discrete map surface


We chose these settings to best display the data because the Depth map would not have been represented as well as either a 2D surface or a Lattice map.  The 3D surface and Grid map helps the user best visualize the underwater terrain.

…a “fun” (you’re having fun, right?) extension would be to adding (Calculate plus) the Elevation map to the Depth map that would represent both the bathometry and the land-based terrain; the challenge would be to identify a color ramp for the display that made sense to the viewer.


Roads map—   

Figure 1-2: 2D Grid Display of Landmap.

Figure 1-3: 2D Grid Display of Roads_Island.

…excellent extended work!!!


To appropriately display the roads present on the island, as shown in Fig. 1-3, first Land_Mask had to be renumbered 0 (Ocean) and 1(Land) for Landmap (Fig. 1-2).  Landmap was then added to Roads for Roads_Island.  By adding the maps together, 0 represented no roads, no land; 1 represented no roads, but land; and 2 represented roads and land.  The default data type was continuous, which needed to be switched to discrete …yep, the defaut display assumes continuous as it doen’t know the number “trick” you are employing.  The shading manager was then adjusted to represent 0 as blue, 1 as green, and 2 as black.


To best represent Roads_Island we chose a 2D Grid Display with the Mesh turned off.  These settings were appropriate given the data types, which were discrete choropleth geographically, and nominal quantitative data.

…very good discussion and presentation


Watersheds map—   

Figure 1-4: 2D Grid Display of Watersheds_Island.

…excellent work!

To appropriately display the watersheds present on the island, as shown in Fig. 1-4, Landmap (Fig. 1-2) was added to Watersheds.  By adding the maps together, 0 represented no land; 1 represented land, 2 represented Target Rock watershed; 3 represented Botany Bay watershed; and 4 represented Sandy Bay watershed.  The default data type was continuous, which needed to be switched to discrete.  The shading manager was then adjusted to represent 0 as blue, 1 as green, and 2 as red, 3 as orange, and 4 as yellow.


To best represent Watersheds_Island we chose a 2D Grid Display with the Mesh turned off.  These settings were appropriate given the data types, which were discrete choropleth geographically, and nominal quantitative data.

…as an extension, you could discuss the “blank gap” between the individual watersheds—why


1b) Considering the Display Form, Display Type and Data Type, which combination would be most appropriate for displaying the following maps in the Agdata.rgs database (explain your choices by discussing the geographic and numeric nature of the data)—


1996_Fall_%Clay map 

Figure 1-5: 2D Lattice display of 1996_Fall_%Clay.


To best represent the percent clay found in the soil, as shown in Fig. 1-5, the most appropriate Display Form/Type is 2D lattice with the Mesh off but the Contour Lines on.  The default Shading Manager settings were not appropriate …they rarely are; don’t even “trust” the base map displays, and the working map displays that are automaticaly generated even worse so they were changed to User Defined range settings of 8 ranges with 2% difference between each range.


These settings were appropriate given that the data was isopleth geographically and ratio quantitative data.


z2000_Image_8_30_NDVI map

Figure 1-6: 2D Grid Display of z2000_Image_8_30_NDVI.




…it is often useful to include the histogram and descriptive statistics for continuous map surfaces as an aid in discussion


The most appropriate Display Form/Type for Fig. 1-6 is a 2D Grid display with the mesh turned on.  The shading manager calculation mode for ranges was set to +/- 1 Standard Deviation with 8 ranges ..great idea as this forces the “weird” edge values into the outlier interval.  The negative data points were colored grey since they are to be considered outliers.  These settings in the shading manager best illustrate the differentiation in vegitation density about the mean. 


Because the vast majority of data was between .65 and .8, a relatively narrow range, a display using equal ranges or count would not provide as much detail in this area as +/- 1 Standard Deviation …good insight.  The settings were apropriate for the data which was continuous isopleth geographically and ratio numerically.


The data found in Fig. 1-6 is isopleth geographically and ratio quantitatively.


Order_III_Soil_Survery map—   

Figure 1-7: 2D Grid Display of Order_III_Soil_Survey.


To best represent the soil survey, as shown in Fig. 1-7, the most appropriate Display Form/Type is 2D Grid with the Mesh off.  These settings were appropriate given the fact that the data was choropleth geographically and nominal numerically ranging from 0-6 representing different soil types.




(1/30/12) Hi Joe-- Sharon and I are a bit confused about the visual exposure maps. For example, on the Vexposure map we're wondering if 1 is the high or low visual exposure range.  Thanks for your help!  Graham


Graham and Sharon— Visual Exposure identifies the number of visual connections at each grid location considering a set viewer locations.  A value of zero identifies a location that is totally hidden from view.  A value of 1 indicates that 1 viewer cell is connected; 2 indicates 2 viewer cells; etc. 


A Weighted Visual Exposure map takes the concept a bit further by not simply “counting” the number of visual connections but “sums” the weights associated with each connected viewer location.  The result is an “importance/influence” calculation for each map location. 


For your “VE enrichment,” keep in mind that there is a Net-weighted Visual Exposure operation that assigns negative weights to “ugly” places and positive weights to “pretty” places so the sum at any map location indicates the overall “aesthetics” value that considers the net condition of ugly/pretty visual connections.


Both of these techniques are contrasted with simple Viewshed calculations that produce a binary map that just identifies if a location is seen at least once (0= totally hidden, 1+ seen at least once).  Joe




(1/25/12) Folks—I am almost done grading …will return the graded reports for Exercise 2 later this afternoon.  A few additional “common” editing things to consider are noted below (still having “fun,” right?  The report preparation is much more than just a map analysis and modeling experience).  Joe


…don’t bold figure titles/captions

…don’t mix italics and normal font in figure titles/captions; also, include a period (my personal preference is italics for figure titles/captions)

…best to put the “color inflection point” (yellow) in the color ramp in the middle for equal ranges contouring

figure tables should fit within normal printer margins (<6.5 inches) or they will be truncated if printed; 8.5” paper width – 1”right margin -1” left margin = 6.5 inches for the body of the report).  Even though Web Layout is the primary viewing form, keeping tables to printer limits will work in all computer environments—even smart phone screens.  From your smart phone, go to and click on the online book Map Analysis and select any topic …the screen display might be small but it fits.




(1/25/12) Hi Dr. Berry-- while trying to give an explanation to part 2 step 2 (coverclumps to coverclumps_size), our group is having some confusion about whether the size operation converts the data between qualitative and quantitative.  My understanding is that quantitative includes: continuous, lattice (optional display type), interval, ratio, and isopleth; while qualitative includes discrete, grid (optional display type), nominal, ordinal, binary, and choropleth data.  Part of the confusion is we don't seem to have a clear understanding of which data is classified between the 2 categories, so my understanding may be incorrect. Any insight you could offer to help us out would be greatly appreciated.  Sharon


Sharon—good question.  The Clump command “uniquely identifies groups of cells with the same value, but geographically separated.  It is most often used to identify contiguous parcels of the same condition on a map. Consider a map with lake cells assigned the value four.  As all of the lakes have the same value, MapCalc cannot distinguish between the individual lakes until they are clumped and assigned unique numbers.”  The Size command “assigns new values according to the size of the area associated with each map category. It calculates the area for entire categories (map values) which are often composed of numerous separate groupings.


The command “CLUMP Covertype AT 1 Diagonally FOR Coverclumps identifies the unique groupings of the three cover types as having five distinct contiguous occurrences.  In this processing, nominal/choropleth data identifying the three cover types (1, 2, 3) is converted into nominal/choropleth data establishing unique ID numbers for each of the five contiguous occurrences (1, 2, 3, 4, and 5).


The command “SIZE Coverclumps FOR Coverclump_size” calculates the size (total number of cells) of each of five clumps.  In this processing, nominal/choropleth data identifying unique ID numbers for each of the five contiguous occurrences (1, 2, 3, 4, and 5) is converted to ratio/choropleth data identifying the size (number of cells) of each of the five clumps (4, 12, 78, 221 and 310). 


The confusion might arise from two fronts—


1) choropleth geographic data type can (and often) has quantitative numeric data type.  A commonly used example is Renumber-ing a road type map (nominal/choropleth) to the average number of windows per hour for each road type (choropleth/ratio).


2) size expressed as “number of cells” involves integer values.  However, if you convert “cell count” to “area” by multiplying times the area per cell (cell size= 328 ft= 100m; 100 * 100= 10,000 sq-meters= 1 hectare) the Coverclumps_Size map’s values fall into a more comfortable continuous range of areas from 4 hectares (4 * 10,000= 40,000 sq-meters= 4 hectares) to 310 hectares which most surly is scaled as ordered numbers with a constant step and absolute reference of 0=no area.  






(1/24/12) Folks—I am in the “throws” of grading Exercise #2.  The following “editing Comments” might useful as you head into your final edits of exercise #3.  Joe


Editing Comments:


…easiest to screen capture just the map area (not the whole MapCalc display window) then “force” the same height to both pasted displays—that way the maps will be the same height and look much more professional


…your screen captures seem to have itsy-bitsy map names way above the map display and legend.  You might try swithing the MapCalc from full screen to an individual window that can be sized.  Also you can right-click anywhere on the map and select Propertiesà Titleà Font, then set to something like “Aerial bold italic 12-14 pitch” and finally choose “use as map defaults”  


…to set some spacing within the “cells” of a table in Word, select the entire table then right-click and  select Table Propertiesà Cell tabà Options and under the Cell margins section, enter…


    …this will set a 0.08 margin around any graphics or text embedded in each of the table’s “cells.”




(1/24/12) Folks—for those of you who have installed MapCalc on your own computer there is a “glitch” in the registration of the software.  Since MapCalc Learner and Academic are now free downloads we have removed the registration program from our server. 


You need to register the program per instructions with the CD once but it will not “officially” complete the registration.  The next time you access the program it will request registering yet again …simply click the “register later” button and ignore the warning of only nine days left.  MapCalc is fully registered internally it just didn’t receive the OK to skip the registration page from the licensing server (because it isn’t there).


Hopefully this hasn’t been a big hassle …I apologize for not mentioning it in class.  Joe




(1/22/12) Hi Joe-- my group is having a hard time displaying z2000_Image_8_30_NDVI map.  We have no idea what the data represents so we can display the data meaningfully.  This includes what we should set calculation mode for ranges and number of ranges.  Thanks, Paulina


Paulina— Google-ing “NDVI” brings up Wikipedia’s definition at  ...a remote sensing technique that enhances living vegetation biomass based on a normalized ratio of the near infrared and visible red spectral bands.  In this case, it is aerial imagery of the field collected via an ultralight aircraft 8/30/2000 at the peak of harvest…



The Shading Manager’s Statistics and Histogram tabs…


…suggest that the data contains decimal points and forms a continuous distribution in numerical space.  With a minimum of -0.0494 and a maximum of 0.835 suggests some sort of ratio. 


The default 3D lattice plot…


…shows dramatic differences along the edges.  Switching the display to +/- 1StDev and setting the tails to grey scale makes another fairly dramatic plot…


…but neither plot is likely the best rendering. 


Your challenge is to “play” with the display settings until you identify a display that “makes sense” to you and write a brief statement supporting your conclusions based on your understanding of the numerical and geographic data types.  Joe




(1/19/12) Folks—more “terribly useful” information …this time about using Outlook.  To make your emails look more professional—


1) Be sure to set your default email composition format to “HTML”…


Start a New Message and select the “Options” tab and then specify HTML


2) Be sure you turn on the Spelling and Grammar checkers


Click on the Windows icon in the upper left corner of the Outlook window and then select “Editor Options” in the lower-right corner of the pop-up.


    …under the “Proofing” item check the appropriate boxes to engage Spelling and Grammar checkers.  You can review and keep/change the other Outlook default conditions (Popular, Display, Advanced, Customize).   Joe




(1/19/12) Hi Joe— do you have a preference on how we name the figures?  For example, do you prefer Figure 1-1, Figure 1-2 or may we use another naming function such as Figure 1, Figure 2, Figure 3a, etc?  Thanks, Alicia


Alicia—my favorite format for figures is…


Figure 1.  Smashed map results based on roads and cover type maps.


…in the standard font/pitch of the main text but in italics and centered under the centered figure itself. 


What is most important is that you use a consistent format throughout the report …consistent font/pitch and margins for the main text; two spaces between sentences; blank line between paragraphs; and centered figure with centered figure number underlined and title/caption in italics.  Joe





(1/18/12) Good morning Dr. Berry— we are having some difficulty discerning the standard deviation thematic display of the Tutor25.rgs Elevation surface in MapCalc.  It does not seem to us that the range values are distributed per standard deviations from the mean. As we understand, 34% of the range should lie within one standard deviation (above and below) of the mean, but this does not seem to be the case. Do you have any advice/wisdom for us?  Thanks, Courtney, Graham and Rob


Courtney, Graham and Rob —great question about the + 1 StDev display mode.  Checkout…


for the background theory—sort of “contouring with a twist.” 


In short, the procedure 1) calculates the Minimum, Maximum, Average and StDev for a map layer (needs to be isopleth/quantitative values), then 2) establishes the lowest contour interval range as from the minimum data value to Average minus 1 StDev.  It then 3) establishes the highest interval range as Average plus 1 StDev to the maximum data value.  Finally, 4) it divides the Avg-1Stdev to Avg+1StDev range into the remaining number of contour intervals specified using “Equal Ranges.”  (Note: use the Statistics and Histogram tabs in the MapCalc’s Shading Manager to identify the Numerical Space metrics you’ll need to check the math).


Hence, when viewing a StDev display the lower (unusually low values) and upper (unusually high values) “tails” of the standard normal curve are matched to the lowest and highest contour intervals.  The more “typical” data values in the center are displayed with more detail. 


A particularly pleasing display is to set the color for the lower contour (tail) to a dark/cool tone (e.g., dark green) and the upper contour to a bright/warm tone (e.g., bright red) with the center contours assigned a color ramp from light green to light red with a yellow color inflection point—give it a try.  I’ll bet it will be the first time you have “seen” a more colorful (and interpretable) rendering of a Standard Normal Curve mapped in Geographic Space


Think about it …map-ematics sort of pulls all that abstract math/stat stuff you learned in statistics down to earth (pun intended).  Maybe this is an alternative way to teach math/stat to folks that don’t easily grasp all that abstract stuff with just a column of numbers (most of us?). 


…now that you have had enough time to fume with an incomplete answer to your question—the “rest of the story” as a follow-up to the theory babble above.  Use the Shading Manager’s Statistics and Histogram tabs to take a close look at the Elevation surface’s “skewed” data distribution (see below) …very “not-so-normal” so why would one expect a good fit of the Standard Normal Curve?  The +1StDev display followed the “normal” statistics ideal—it’s just that the ideal of normally distributed mapped data is not always the case.  Can any of you suggest an alternative method for “contouring” the skewed data that has a statistical foundation?  …maybe something to do with the Median and Quartile Range?   Now that would make good “extended discussion” and master’s degree fodder.  Joe  





(1/17/12) Hi Professor— Sorry to bug you about this again, but while working on the lab on my PC I ran into the same problem with the temporary file error when I tried to run the Erosion_Codes step. How do I change my administrative privileges so I can accomplish this step?  Thank you, Sharon


Sharon—you need to login as administer (likely not the user you normally use or you would have full permissions) and then set full permissions for the user you normally use.  MS instructions are posted at  The instructions in the following video might help as well…


If problems arise we can tackle them on Thursday.  Joe





(1/17/12) Hi Joe— my group is having trouble on deciding what to say for the discussion in question 5 step 3.  We don't know the units for the Flowmap …a count of the number of uphill grid locations from the legend and how to describe what the process is from elevation to flowmap. Could you give us a hint? …see the description of Drain function below. It is much easier to explain the Flowmap once it is renumbered and called Flow_ClassesRENUMBERing generalizes the detailed flow information (isopleth quantitative (ratio) data) into just three classes of increasing surface flow accumulation (choropleth qualitative (ordinal) data).  Thanks, Paulina


Paulina— Drain is a rather unfair step as we won’t study “flow accumulation” until the Distance drawer in the Spatial Analysis toolbox (week 4).  The Drain command creates a map indicating the number of steepest paths (optimal path density) from a set of locations along a surface.  Since you specified the Entire map as the “SourceMap” the routine will sequentially identify the steepest downhill path from every grid location while keeping a running sum of the number of paths crossing each map location—total number of uphill grid locations contributing surface flow to each map location.


In the exercise the Flowmap has a skewed data distribution from 1 (rain drop landed but didn’t flow anywhere) to one location that has 200 uphill contributors …checkout the Histogram and Statistics tabs in the Shading Manager.  Hence, the default display using “Equal Ranges” is very misleading …try switching to “Equal Count” as the calculation mode in the Shading Manager.


You can get a quick summary of any command using the Help button in its dialog box (see below); a more detailed description in the MapCalc Manual.   Joe




…pressing the “Help” button on any command GUI will pop-up a description of the command function, options and syntax.  The Drain command Help pop-up description of its function is…




Drain creates a map indicating the number of steepest paths (optimal path density) from a set of locations along a surface. It calculates all downhill paths extending from a starting location specified on one map (sourceMap) over a three-dimensional surface (surface map). The surface map may be a topographic surface map, a cost surface map, or any other map in which the cell values are represented as height.


This function differs from the Stream function, in that paths are calculated from all target cells rather than just a single cell.”





(1/11/12) Hi Joe— I noticed that we do have some display options on font and formatting for the display of the map, but I have yet to figure out how to close the gap between the map image and the legend and I don't see a place where you can change the distance. Am I missing something?  Thanks, Alicia


Alicia—keep in mind that “cartographic niceties” are a bit limited in MapCalc.  Serious users export a final map to a commercial system like ArcGIS for fancy displays and plotter printing.


The distance between the legend and map display is dynamic and can be sized by switching the MapCalc Window from full screen to “restore down” ( center icon in the extreme upper right corner) and then click/drag the edges of the window to size.  The great thing with SnagIt is once you have the display proportioned the way you want it, SnagIt will automatically capture the window no matter where it is placed on the screen.  The only got’cha is that you have to remember you favorite sizing if you want to duplicate after you close a MapCalc session and reopen at a later date.


Most of the map display options are in the Shading Manager pop-up (double-click on the map Legend) but more options are in the Map Properties pop-up (right-click anywhere in the map display and choose Properties)…


…under the Title and Legend tabs you can set the font and position.  Joe





(1/11/12) Folks—in anticipation that some of you might be having some troubles getting into the swing with SnagIt (I haven’t received Exer0 from all of you; please send my way when completed), I have included below an email dialog thread from a couple of years ago that might be helpful.   Joe



Using Snagit – Basic Procedures


Snagit [download and install from the Internet — screen capture software; 30 day evaluation; see for information on fully licensed system ($37.95 Academic version)]


Once you have downloaded, installed and launched SnagIt, switch the program to “Compact” mode by selecting menu item Viewà Compact View.


The “Mode” drop-down list is used to set the type of capture. The most common setting is “Image Capture” to generate a screen grab that is sort of like taking a photo of the screen or portion of the screen that you can paste into Word documents and PowerPoint slides. The “Video Capture” mode can be used capture screen animations but the video file generated has to be hyperlinked into documents and PowerPoint slides.


The “Input” drop-down list sets the type and properties of screen captures. The most commonly used type is “Region” that enables you to click-and-drag a rectangular box around a portion of the screen. The “Window” capture type is used to capture windows on the screen that are highlighted as you move the cursor. The other capture types are less frequently used. The “Include Cursor” option is used to capture the mouse pointer in an image capture.


Under the “Tools” drop-down select “Program Preferences” and in the “Hotkeys” tab you can select the key combination to activate SnagIt for capture. This sequence is normally “Ctrl + Shift + P” but can be changed if it conflicts with another programs hotkeys assignment.


Now you are ready to capture screen images. Simultaneously press the keys “Ctrl/Shift/P” and the capture cursor will appear. Left Click-and-Drag a box around a portion of the screen then release the mouse button and the SnagIt Editor with the captured portion will appear.


There are numerous tools for adding text, drawing on the figure and special effects.


But for your first capture, simply click on the “Green Checkmark” in the upper right corner to transfer the image to your clipboard.


To embed the clipboard image into a Word document of PowerPoint slide, click at the location you want the image placed and press the “Paste” button (or simultaneously press the Ctrl/V keys).


For a professional appearance in a report, Resize and Center the image, and then add a Centered Caption in italics underneath it to set the figure apart from the rest of the document. For example, screen captures of Lattice and Grid displays of Tutor25.rgs Elevation data would appear as—


Figure 1-1. 3D Lattice Display. Note the smooth appearance of the plot that “stretches” the grid pattern

by pushing up the intersections of the grid lines.


Figure 1-2. 3D Grid Display. Note the chunky appearance of the plot pushes up

the “pillars” representing each grid cell border.





(1/11/12) Folks— I haven’t heard much from you.  The assignment must be clear as a mountain lake and responses intuitively obvious …great!  Or you are spinning your wheels and having trouble getting traction on what it is you are supposed to do …and worrying how you are going to get it done by 10:00pm Thursday.  If this is the case, let me know your roadblocks and together I bet we can get your team out of the ditch.


On a brighter note, at least one team has completed their report and commented that “…we make a great team! What I like about the group and this report is that we discussed each question to make sure we understood it.  Communicating this way is time consuming, but at the end of the report I felt like we really knew the topic.”  Your bright testimonial awaits.


Be sure that you individually (complete anonymity) complete the Team Evaluation Form posted on the class website within 24 hours of turning in the report …example below.   Joe





(1/10/12) Hi Joe-- are the reports for both Exer 0 and Exerc 1 due by 5pm Thursday? Also, would you prefer a separate Word document with the answers to questions and necessary images or should we provide the report within the template of the exercise document already provided? Thanks, Alicia


Alicia—both Exer0 and Exer1 are due 10:00pm Thursday which gives the team a chance to meet with me to “polish” any last minute concerns.  Don’t spend more than a few minutes on Exer0 as it simply “documents” that you were able to access MapCalc using the Tutor25.rgs database and use SnagIt to screen grab a map display …skills required in tackling Exer1.


Also, keep in mind the team can request a “no penalty” extension anytime before 12:00noon Thursday.  Send me an email requesting the extension and identify a new fixed date/time due date (e.g., “…we had difficulty getting our schedules to mesh. We will submit the report by 12:00noon Saturday”).  Keep in mind that compounding extensions is not a good idea and the team should judiciously reserve the “extension card” for true times of need. 


I plan to keep the same teams for Exercise #2 but shuffle team membership for Exercise #3 …shuffle every two weeks


I prefer you use the report template (Exer1.doc) and “simply” embed your responses, screen captures and further discussion at the appropriate locations as noted in the report template.  In the past most teams have a final “group writing session” (either eyeball-to-eyeball or via email) where rough drafts of the report sections are edited and combined into the final report for submission.  


The experience is intended to simulate a group report to the boss in the real-world (e.g., a consulting company) …not an academic lab report or a paper.  Within this context I strongly encourage the team to review the Report Writing Tips item on the class website.  Also, review the Guidelines for Preparing Homework Assignments and Submitting Homework Assignments items in the Syllabus posted on the class website.


The bottom line is that I expect the reports to be of professional quality both in content and form …be sure that Word’s Spelling and Grammar checkers are turned on.   Joe




(1/10/12) One question we did run into was interpreting the legend on the renumbered maps.  To use the renumbered road_proximity map as an example, the new legend was between 1 and 9, I believe (I don't have it directly in front of me) and most of the new map was 1.  On the renumbered slopemap, 1 was desirable and higher numbers were less so.  Is the same true for the road map/all renumbered maps or are we missing how to interpret the new data?  I can interpret what the data means before it has been normalized, but I guess I'm confused  on how to interpret the data afterwards.  Thank you!  Michael


Michael—your question about the calibration step is a good one.  The RENUMBERing (RECLASSIFYing in Spatial Analyst) to a common “goodness” range of 1= least suitable to 9= most suitable is a form of normalizing the map variables.  The data ranges and units of the Base and Derived maps are all different—the RENUMBERing transforms them into a consistent range so the averaging of the Interpreted map layers makes mathematical sense (dare I say map-ematical sense?).


An important point to remember is that the “algorithmic” processing step from Base to Derived maps keeps the map values within the “fact” realm (e.g., slope, proximity and even visual exposure) that remain facts on the landscape.  The “calibration” processing step, on the other hand, moves the map information into the “judgment” realm …from physical to cognitive maps. 


In suitability modeling, the “calibration” step is often dicey and calls into play “expert opinion” or empirical research.  However, the “weighting” step is the most ephemeral as it plays to human values.  To weight one map layer more than another is very subjective and evokes personal perception and experience camper might opine that good views of water is ten-fold more important than aspect direction while another might believe just the opposite.


Most successful suitability applications like campground location use expert opinion to “calibrate” and participatory interaction of end users to “weight.”  There are numerous quantitative techniques in social science for assessing group thought …we will touch on two (Delphi and AHP) that are widely used when we discuss modeling in the sixth week.


The bottom line of your campground suitability experience is that maps are being used in non-traditional ways for “thinking with maps.”  Grid-based map analysis and modeling are providing the tools but domain experts (vs. GIS experts) are steering the ship.   Joe





 (1/9/12)  Folks— a few “logistical” items…


1) VERY IMPORTANT …in the GIS labs, it is imperative that you access the MapCalc database (Tutor25.rgs) and script (Tutor25_Campground.scr) from your student drive (Z:drive) or a USB pocket drive that you plug into the lab computer as the multiple-user environment in the lab has special “write permissions.” 


If for some reason you experience a “write permission fatal error” while executing MapCalc in either of the GIS Labs using your Z:drive or pocket drive for the data, move to another computer and send me and Steven Yee ( an email noting which lab and computer had the problem.


The alternative is to load MapCalc and the class database (\GISmodeling\MapCalc Data) on your own computer (any Windows PC or Mac running in a Windows environment) and use it for the exercises and report preparation.  See the instruction with the text CD for installation of MapCalc and the Setting up and using class data item on the class website.


As you work through Exercise#1, let me know any questions (concerns or complaints) and I’ll get an email reply back to you as soon as I can. 


2) Christian has dropped the class, so one team has only two people (a blessing when scheduling team meetings and not a problem).  Please send a list of the current team membership.


3) The class photo with student statements is posted at… . 







(1/6/12)  Folks— before you start using MapCalc, I encourage you review the two short demos (a few minutes each) on MapCalc basics and example operation that are posted at…, Short Video Demos viewable online or download


Billy Gates will warn/scare you about not executing the demos but I assure you that they are virus free so be persistent in telling him you want to “run” the executable.


Also, you ought to check out the annotated Campground Model example posted at…


before you begin your report preparation.


This year the exercise is particularly unfair as I mistakenly skipped the slides describing the campground logic used in Exercise #1 when we returned from break (oops)…



What I had planned to say was that the logic of the campground GIS model can be expressed as a “simple” flowchart of processing with the rows identifying the criteria employed in the model (slide 24).  Best locations for a campground are thought to be…

·         Gently sloped so a family of five won’t roll down the hill.

·         Near roads, so access is easy.

·         Near water, for fun and fishing.

·         Good views (of water) for added visual enjoyment.

·         Westerly oriented so tired campers can sleep-in late.


The columns in the flowchart represent existing and derived map layers of increasing levels of abstraction from left to right (slide 25)…

·         Base maps of Elevation, Roads and Water depicting physical things that can be objectively measured and inventoried.

·         Derived maps of Slope, Proximity to Road, Proximity to Water, Visual Exposure to water (how many water cells can be seen from each grid cell location and Aspect (in N,NE,E,SE,S,SW,W,NW octants and no aspect for perfectly flat areas).  The transition from Base to Derived maps use map analysis tools, hence it is termed “Algorithm.”


Note: Base maps are most often directly measured and Derived maps could be measured at each grid space as they arte real-world conditions (Abney level to measure slope; surveyor chain to measure proximity to road and water; ocular estimate for proportion of water; compass for aspect), but it is much easier to use a computer algorithm to derive the information for each of thousands of grid locations. Hence Derived maps using algorithms (map analysis “tools”) are a bit more abstract in nature than base maps. So just how does the software calculate visual exposure (Radiate command) …that detail is reserved for week 4.


·         Interpreted maps of preferred slopes (S-Pref), road proximity (R-Pref), water proximity (W-Pref), views ((V-Pref) and aspects (A-Pref).  This step is monumental as it represents a huge jump in the level of abstraction from “facts” on the landscape to “judgment” about what are good and bad conditions for each of the model criteria.  There isn’t “goodness for campground meter” that you can poke in the ground …that involves human judgment and values interpretation of conditions.  The process is analogous to a professor grading papers with a possible interpretation of “goodness” from 1= crummy to 9= awesome.  This process is termed “Calibration.”

·         The final Modeled map combines the five criteria expressions into a single, overall expression.  This is analogous to a professor compiling a final grade by averaging the grades on each paper (viz. criteria rating in place of a paper grade) for each student (viz. each grid cell location in place of each student).  This process is termed “Weighting” as a weighted average is often used that recognizes differences in criteria importance.


The red labeling in slide 25 denotes the MapCalc commands that executes the processing from left to right. 


Slide 26 shows the command script that you will use in the exercise.  Your challenge when running the model (Tutor25_Campground.scr using the Tutor25.rgs database pursuant to the instructions in Exer#1.doc) is to…

1) double-click on the first command line (Slope Elevation fitted FOR Slopemap),

2) note/appreciate the information in the pop-up dialog box,

3) press the Help button to get information about the command function and syntax (more information in the MapCalc Manual that is posted on the class website for down load as a .pdf file), and finally

4) press the OK button to submit the command.  The new map will automatically be displayed (the “Slopemap” for the first command line).  Right-click anywhere on the legend in the map display and more information will pop-up. 


Continue executing the model by successively double-clicking on the command lines one at a time (individual processing steps); top to bottom (processing order).  Enjoy the show BUT DON’T MESS WITH ANY OF THE SETTINGS in the dialog boxes or legend shading manager tables …you will have ample time (way too much?) in subsequent exercises to be reckless/creative.  This first encounter with MapCalc is a “tricycle level” exposure.  You will be at the BMX racetrack in due time, provided you don’t break your neck on this toddler ride.


The real objective of Exer#1 is at a intellectual level higher than mechanics …to get you thinking about the connection between the campground model logic (flowchart) and its expression as map analysis steps (commands) that transition base maps into a modeled map.  As you progress through the exercise you will be asked to capture screen displays using SnagIt and paste them into the Exer#1 template report at the appropriate places.  Also you will be asked to explain what you think is happening at each processing step …sort of an unfair toss into the deep end of the pool.  But the task is doable if you concentrate on how the numbers on the maps change (not the colors in the display).  All grid-based map analysis involves deriving new map numbers from old map numbers—everything is in the numbers!  


Shoot me an email if your team hits the wall …I bet a short return email will easily right the tricycle.  If not, we can always set up a Go-to-Meeting session where I can in real-time button pressing lead you through the rough spot.  Also, keep in mind that I am on campus by 10:30am on Thursday so we can have eyeball-to-eyeball exchange to polish any trouble spots in your team’s report or you just want to chat.  Send me an email to set up a meeting time or drop by 3-6pm before class for open-door hours.


We are having fun, right???  Joe





(1/5/12) Hi Joe …this is Paulina Kruse.  I am a junior at DU.  I was having second thoughts about taking your class this quarter.  I did talk to my adviser and he said I would be fine taking this class without taking the Introduction to GIS class.   I still feel like I don't have much experience but why not start now? I haven't quite determined my specific interests in the GIS world yet, but it was the use of technology and visual layout of information that has caught my attention. I like to learn new things, and work hard.  I expect to learn a lot in your class and I might discover my interests in GIS. 


See you tomorrow, Paulina


Paulina—the material presented does not require a GIS background …more an interest in quantitative analysis (basic math/stat) and an ability to visualize spatial problems.  The course is taught at an upper-division/grad level pace with weekly team reports that is a fairly consistent demand on your time.  It focuses on grid-based map analysis and modeling, not traditional GIS mapping—more “thinking with maps” than producing map products.


I have taught a similar set of concepts in the JETS (Junior Engineers and Tomorrow’s Scientists) intercity program and numerous 2-5 day workshops for professionals from a wide variety disciplines and backgrounds, such as managers, administrators and staff in most of the USFS National Forest offices.  Most of the attendees find the concepts, approaches, procedures and considerations both interesting and useful; very few find it “over their heads.”


What is different from these instructional environments and the GIS Modeling course is that we have 10 weeks following fundamentally the same lecture material but added time for students to delve into “hands-on” experience with various options, extensions and more detail into how the operations work …or when they don’t work (limitations and inappropriate use).  The team reports are what elevate the course to UD/Grad level.  Joe





(1/4/12) Dr. Berry-- I am currently enrolled in your GIS modeling class, however, I am an anthropology student taking classes outside of my department and am trying to make the decision on whether I should be formally enrolled in your class or perhaps audit it (should you be agreeable to such an arrangement).  I have taken 2 GIS courses at DU prior to yours because I intend on using GIS in my master's thesis.  I have some questions about the class itself and some issues concerning my thesis and I was wondering if you would have some time to meet with me before class tomorrow, I will be on campus all day and can meet at any time that is most convenient for you.

Thank you, Christian Driver


Christian— the weekly course load is estimated at about 1) two hours required reading 1) three hours lecture and 3) six hours team reports ...about eleven hours total.   If you haven’t had a chance, I encourage you to check out the class website at…

…for a description of class content and logistics. 


Generally speaking, the course focuses on grid-based map analysis and modeling tools and procedures.  The white paper…

    An Analytical Framework for GIS Modelingwhite paper presenting a conceptual framework for map analysis and GIS Modeling

…serves as a good overview of the course material.  A shorter and less didactic description is posted at…

    Beyond Mapping III, Topic 24 Overview of Spatial Analysis and Statistics


I am open to your auditing the class (Thursday evening lectures and readings?) but most of the learning occurs by completing the weekly team reports that provide “hands-on” experience with the concepts, procedures and applications.  Auditing would develop a basic appreciation of the capabilities and considerations involved in GIS modeling but likely not the “skill level of understanding/experience” that you would need to translate the approaches to your thesis research. 


I would be delighted to meet with you tomorrow (Thursday) to discuss your objectives and the course further.  My normal office hours are Thursdays 3:00 to 5:00pm on but my trek from Fort Collins usually has me on campus by 10:30am.  Let me know your best time to meet.  Joe





(12/10/11) Folks—I am delighted that you have enrolled in GIS Modeling for next term. 


Please send an email ( that briefly outlines your background, interests and objectives in taking the course.


I encourage you to check out the class syllabus posted at  for more information on the course format and requirements.  Note that homework exercises are completed in 2-to-3-person teams and are completed outside of class.  Please send an email to me with any questions or needed explanation of any aspect of the course …I’ll share the Q/A by posting on the “Email Dialog” item on the class website. 


Since the class is fairly small and my Blackboard skills limited, I prefer to run the course through my own server.  I will establish a limited BlackBoard course outline but it will simply “bounce” to my server.  


Some logistical announcements…


-         The Class Website is posted at and contains all materials supporting the course including syllabus, schedule, reading assignments, and exercises.   


-         The Map Analysis textbook ( will be available at the 1st class meeting for the author's discount price of $34.64, cash or check payable to Joseph K. Berry.  The companion CD contains the MapCalc, Surfer, and Snagit software we will use in the course.  If you want to get a copy of the book/CD before the 1st class meeting, check with Will in the Geography Department office.


-         The online links for the Readings for the 1st Class are posted on the class website at  Be sure to read the paper that presents a conceptual framework for map analysis/modeling that will be used in the course.  As the course kickoff approaches I will post the PowerPoint on the class website.


-         The BASIS website at contains additional materials and papers supporting the course.  Of particular importance is the online book Beyond Mapping III posted at containing extended discussion of material presented in class and the textbook.  The "Chronological Listing" link identifies articles published since the Map Analysis textbook (2007).


Have a great set of holidays!!!  See you in January.  Joe





 (12/8/11) Dear Dr. Berry-- My name is Courtney Hall. I am a first year graduate student in ecology and am interested in taking your course.  Is this an advanced GIS course? Or, could a student understand and excel in the course if they have no GIS knowledge?  I have no GIS experience, but I think that this would be a good course for me. I am interested in restoration ecology and conservation ecology.  Is there anything else that a student should know prior to taking this course?  Kind regards, Courtney Hall


Courtney—my educational background is in natural resources management which pioneered many of map analysis techniques and applications …not mapmaking.  Developing skills in analytical procedures for understanding spatial patterns and relationships impacting natural systems seems keystone to ecology— the GIS Modeling course focuses on these procedures.


Data nuances, structures, formats, and acquisition, as well as display and geo-query/retrieval, are major elements of an introductory GIS course.  These concepts and practices are the bedrock of GIS, but in GIS Modeling we focus on “maps as numbers,” presume that are data is “perfect” and basic cartographic procedures are reserved for final map display.  The emphasis in the course is on “thinking with mapped data” and “spatial reasoning” which do not require a deep keel of understanding of mapping techniques as we focus on the analytical concepts and applications.  The bottom line is that you don’t need a prior GIS course but you do need to be 1) comfortable with basic math/stat principles that we will apply to digital mapped data and 2) a bit of fortitude as the workload of the course is at the upper division/grad level. 


I encourage you to check out the background reading for the first class…, under Course Readings item


…as well as…, SpatialSTEM Has Deep Mathematical Roots, A Quick Peek Outside GIS’s Disciplinary Cave   


The main thing to keep in mind is that while the material presented doesn’t require prior GIS experience or advanced perquisites, the course is taught at the upper division/graduate level making the demands fairly substantial (about 10-12 hours per week) with weekly team reports, readings, directed mini-project and a couple of exams that keep students busy throughout the term …the pace makes getting behind tough to catch up.  Joe





(11/26/11) Hi Dr. Berry— I'm thinking of enrolling in your GIS Modeling class next quarter and I have a few questions. I heard from a couple of people that you teach a good modeling class, but I seem to remember them mentioning some 3D stuff. Were they describing another course you teach? I have a lot of experience with ArcGIS so I'm looking for more of an advanced course to learn about expanding the software functionality rather than performing standard site-selection exercises. Do you happen to have a syllabus you could send me so I could see if the class might be what I'm looking for? Thanks for your help!  -Alison Terry


Alison—the class website has the course Syllabus and other materials…


The 3D experience in the class involves data visualization of mapped data surfaces, not “landscape visualization.” Checkout…

Topic 18 Understanding Grid-based Data


…in the online book Beyond Mapping that serves as optional reading beyond our basic text.  3D is used to visually explore the spatial distribution of mapped data layers to better understand the spatial patterns and relationships in continuous map surfaces.


We do not use ArcGIS in the course but there is a cross-reference to Spatial Analyst/Grid operations for the analytical tools used in the course—the focus of the course is on map analysis and modeling concepts, procedures and considerations, independent of software system.  To give you an idea of MapCalc software we use, check out the short videos at…


Let me know if additional questions or thoughts arise.  Joe


P.S.—I post most email responses of potentially general interest to Email dialog and other helpful hints item on the class website—this might be a useful resource to occasionally check out in case other potential students have questions.





Course Content and Who Wants to Be a GIS Modeler?  


Joe-- Who do you feel is your ideal student? Someone who is planning to continue using GIS as a career choice or someone that wants a good solid understanding and competence of use of GIS? At this point I’m not planning to go into GIS as a career, but I would like to be competent enough to use it to my advantage for career placement.  Will you be covering ArcGIS?  Thanks, Hilary (CSU, 2006 …answer hasn’t changed)


Hilary-- students who are interested in learning concepts/procedures/considerations in analyzing spatial relationships are best served they GIS specialists or domain experts (researchers/managers) with an interest in developing new applications.  Previous classes have been successful mixtures as both domain expertise and GIS skills are needed for effective modeling. 


The idea that GIS is a cluster of technical specialists who are “down the hall and to the right” is evolving into a collaborative team solving spatial problems (versus warehousing and displaying static map data).  This course anticipates where geotechnology seems to be heading ...a fabric of our society used by a wide and diverse community of folks.  This perspective suggests less flagship/toolbox software systems and more custom/tailored packages solving well-defined spatial problems (with users not even knowing they are using a GIS).  Not so many years ago spreadsheet analysis and database management was the sole arena of computer scientists …now these tools are in the hands of anyone with a PC, basic understanding, interest and a problem to solve.


We will not be using ArcGIS directly as it is a fairly large and complex system that has and a steep learning curve in mapping, database development and spatial database management that must be negotiated to use it in learning concepts, procedures and considerations underlying grid-based map analysis.  This would limit the class to GIS specialists and the amount of map analysis material that could covered.  The fundamentals of map analysis involve spatial reasoning skills that are independent of the software used would be like demanding separate statistics courses for Statistica, SPSS, SAS JMP, etc. software environments.


However, all of the MapCalc and Surfer operations we will be using are cross-referenced to ArcGIS operations and those with this background should be able to translate the concepts, procedures and considerations they learn to the command syntax of the ArcGIS environment (Grid/Spatial Analyst, Geo-statistical Analyst, Image Analyst and 3D Analyst extensions). 




P.S.—more on GIS Education “philosophy and approach” is in the online book Beyond Mapping III, Topic 4,Where Is GIS Education?” posted at