This page has an interactive version of Figure 3 from the paper. It is a Wolfram Mathematica CDF. If you do not see controls and a figure, please see the note at the bottom of the page. Or, you can try the version available here that should work without installing anything (if your browser and settings allow javascript). A few comments:
The top portion has a legend and controls used to change the parameters and prices. The legend is color-coded, but also describes the location of the four regions in the figure. Remember that changing the parameters or prices may make a region cease to exist (e.g., if you increase the price for credit purchases at merchant 1, no customers will chose this option, causing this region to no longer exist and thus to no longer appear in the figure). You can also change the opacity of the shading.
The first panel with "slider" controls allows you to change the cash back bonus paid to (β>0) or fee paid by (β<0) customers who use the credit card. The second and third controls in the top panel allow you to change the width of the distribution of customer preferences over merchants (changing the width of the figure) and over payment forms (changing the height of the figure). The next two panels of controls allow you to change the prices set by the merchants for purchases completed by debit and credit. The third control allows you to set directly the surcharge on credit card transactions implied by the credit card price instead of setting the credit card price itself. You can close each of these sections by clicking the little arrow next to the heading.
The second to last panel of controls allows you to change the bounds and the step size for the "sliders" used to change the prices (e.g., so that they drag more slowly or quickly). The last row of controls has a button to reset everything and to change the size of the entire figure.
If you would prefer to have the controls to the left of the figure, click here.
If you encounter any problems or difficulties, or if you have any questions, please feel free to contact me.
If you do not see the figure above this note, you need to install the free Wolfram CDF player from the Wolfram website. It is free, but there are a few things you might want to know before downloading and installing it. First, the page will likely tell you "A newer version is available." It tells me this every time, no matter what browser I use, and even if I just downloaded and installed the new version. Because Mathematica does not have bugs, only "features," the only reasonable conclusion is that Wolfram updates the CDF player more quickly than it is possible to download and install it. Which brings me to my next word of warning: the installation file is quite large (around 192MB when I wrote this). It is so big because it includes much of the functionality of Mathematica, so it is not entirely a bad thing, but it is something you might want to know ahead of time. Third, they make you enter an email address to download it. Yes, they will email you in a few days and ask how you like it and suggest you use and buy Wolfram products, but a "communal" email address (e.g., test@test.com) works. Lastly, you have to restart your browser when it is finished installing. Those are the disclaimers. Despite the many frustrations with Wolfram (e.g., the lack of an undo feature), Mathematica can do quite a lot and so can this CDF player, so it is not a bad thing to install unless you are very short on space. Here is the link again to install it.