Practical Data Analysis with JMP®

Using JMP to Estimate a Population Proportion

We already have a data table of individual incident reports. In this section, we'll analyze the data in two ways. First, we'll see how JMP creates a confidence interval from raw data in a data table. Next, we'll see how we might conduct the same analysis if all we have is a summary of the full data table.

Working with Casewise Data

1. Open the data table Pipeline Safety.

2. Select Analyze → Distribution to summarize the IGNITE column. Your results look like Figure 8.1, which was prepared in Stacked orientation to save space.

For 25 incidents in the table, we don't have information about whether or not the gas ignited. In the remaining 443 incidents, nearly 81% involved ignition. It is fairly common to ...