This page has an interactive version of Figure 3 from the paper. If you do not see a figure on this page below these notes, please see the note at the bottom of the page. If you do see the figure, here are a few comments on it:
There are two sections, one with controls and one with the figure. The controls (buttons) allow you to change the parameters and prices.
The first row with buttons 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 rows of buttons allow you to change the width of the distribution of customer preferences over merchants (changing the width of the figure) and over payment forms ("wallet" preferences, changing the height of the figure).
The next two panels of controls allow you to change the prices set by merchant 1 and 2, respectively, for purchases completed by debit and credit. The third row in each panel 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.
The next panel has a legend describing the regions shown in the figure. It is color-coded, but also describes the location of the four regions in the figure in case the colors are difficult to distinguish. 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 by enough, no customers will chose this option, causing this region to no longer exist and thus to no longer appear in the figure).
If you would prefer to have the controls above the figure, you can click the button at the bottom that says "Swap Horizontal/Vertical Layout". The "Reset" button returns the parameters and prices to their initial values.
You can also try a version written in Mathematica 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:
First, keep in mind that I am an economist, not a web developer. I just taught myself enough HTML5/javascript in part of a day to get this to work (and to work within Google sites). I tested it on several different browsers and operating systems, but it is not fully robust and might not work for everyone. If you do not see the figure, there are a few things you can try:
If your browser blocks javascript, try enabling it.
The figure you should see uses javascript and an HTML5 canvas inside a Google site "HTML Box." Google's "HTML Box" is not perfect. You can try an alternative version that uses a Google Apps Script instead. It loads onto the page differently, so it might work if the version on this page does not, but the code itself is the same javascript and HTML5 canvas so it probably won't help. The Google Apps Script version might only work in Google Chrome. It is available here.
If neither of these works, there is also a version written in Mathematica, available here. Even if the version on this page does work, the Mathematica version is usually faster once it loads and it is easier to change the parameters and prices. It does require, however, that you have the free Wolfram Mathematica CDF player installed. There is a note at the bottom of that page about how to install it.