Originally I programmed the empirical distribution with a discrete distribution in mind, so I just left that in the program. With the empirical discrete, the sliders represent observed frequencies for five values (the 5 sliders). With the empirical cumulative, the sliders represent 5 observed values in a cumulative distribution, and we interpolate values in between as described in our book.
For Weibull, I worked with the form of the function given by Wikipedia, which has parameters k and lambda.
Triangular is just as described in the book. The C value needs to fall between the A and B values. In the regular version of the program, you are prevented from running the triangular program if these requirements are not met, and there is an error printed to the console. The applet has no console, so be sure to set the values such that A < C < B.
For more, please see the in-line comments in the nlogo file.
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