Question

What does the 'P' in "p-chart" refer to?

Answer 1

In statistical process control, a "p-chart" typically stands for a "proportion chart." The "p" refers to the proportion or percentage of defective items in a sample or process. P-charts are commonly used to monitor the stability and consistency of a process when the data being measured is categorical and can be classified as either conforming or non-conforming.

Answer 2

The 'P' in 'p-chart' stands for the proportion of defective items in a process, and the chart is used in statistical quality control to monitor this proportion.

Step-by-step explanation:

The 'P' in "p-chart" refers to the proportion of items in a sample that are defective. A p-chart is a type of control chart used in statistical quality control for monitoring the proportion of defective products or services in a process. It is based on the binomial distribution, as defects are either present or not (success/failure).

To calculate the values plotted in a p-chart, we use the formula p' = x/n, where p' is the estimated proportion of successes in a sample, x is the number of successes, and n is the sample size. The control chart will have this proportion on the vertical axis, with sample groups on the horizontal axis. The p-chart helps in determining the stability of the process by revealing any variations that may indicate problems with quality control.