This lab presumes an understanding of certain basic concepts, which were covered in the lecture material associated with this module:
Lab Objectives:
In this lab, you will
UMich Students: save it to c:\temp.
Run the demo provided, of cholera. Take all the defaults, don't intervene, etc.
You will also want to make a note of the total number of deaths (on the screen following the S-shaped curve screen). We will use these to create a comparison of simulations, based on differences in the parameters of hierarchical versus contagious diffusion.
Use this web form to add your results to those of other students.
Here is the result file, if you want to check back later (you might be the first one to give some result!). Reload the file to see any updates.
You might try a few other choices of contagious versus hierarchical diffusion parameters, to augment our communal data file.
The software writes a file called diffuse.out in the directory containing the Diffuse executable. Be sure to save the file diffuse.out once you've chosen a simulation to explore further, however, as it is overwritten each time Diffuse runs.
We will now turn this output file (diffuse.out) into a set of files which can be used in either Stat!, GeoMed, or Gamma software (although we will only use the Stat! and GeoMed files). You will need to upload the file diffuse.out to a web-based converter: it will produce zip files containing the input files you need. Save the Stat! and GeoMed zip files to your computer.
Use the web-based converter now.
Choose pnt files based on the S-shaped curve for your particular data set: at what timestep was the epidemic taking off? At what timestep was it leveling off?
Do you discover that there is a radical difference for some pnt files between the results obtained for the Moran's I using the two different types of contiguity matrices? Do the results jive with the parameters you chose for the different types of diffusion (i.e., if you selected a small contagious diffusion component and a large hierarchical coefficient, is this reflected in the behavior of Moran's I depending on contiguity matrix?
UMich Students: First download, and install GeoMed to the c:\temp directory.
![]() |
The lower-left and upper-right corners correspond to the most populated areas in his clustered population distribution. |
Page by Andy Long. Comments appreciated.
aelon@sph.umich.edu