Run Length

Run Length

In this sampler model, a coin is flipped once (Draw = 1) and repeated 50 times (Repeat = 50). The attribute RunLength computes the number of times that h's or t's occur in a row.

Running Difference

The RunningDiff attribute adds 1 to a running count for every trial in which a specified element occurs and subtracts 1 for every trial in which it doesn't occur. In the example of coin flipping, the attribute RunningDiff_h shows how many more (or fewer) times h has occurred than t. The plot graphs this attribute on the vertical axis and the RepeatIndex (or trial number) on the horizontal axis. RepeatIndex was added by checking the corresponding option in the Results Attributes panel. In the graph we see that early on, the numbers of h's and t's were staying fairly close, but then about half way through, hs began to run ahead of tails.

Running Count

This attribute computes, over repetitions, a running total of the number of times the specified element has occurred. Add it to a results table by checking the corresponding option in the Results Attributes panel.

Running Percent

This attribute computes, over repetitions, the running percent of occurrences of the specified element. Here we flipped a coin 200 times and graphed the percent of h's over repetitions. Note that as the sampling progressed, the percentage of h's tended to get closer to 50%. This type of graph is often used to illustrate the Law of Large Numbers. Add RunningPercent to a results table by checking the corresponding option in the Results Attributes panel.

Repeat Index

This creates an attribute showing the repeat number for each case within the run. Add it to a results table by checking the corresponding option in the Results Attributes panel.

Run Index

This creates an attribute whose values are the run index. So the first time you click RUN, the run index is 1. The next time you click RUN, the run index is 2, and so on. To reset the run index number, click the Reset button in the Results Attributes panel.