I have had frequent run-ins with non normal data and this continues. This time the scenario is different and I need your advice on handling such data.
I was trying to perform the capability analysis of an injection molding process. I have 24 data points. I started by checking the normality of the data and it turned out to be non normal. I tried to find the best distribution on Minitab but none matched since the p value for all distributions was far less than 0.05. The data could not be transformed using the Johnson's transformation also. While reviewing the data I realized that the values are closely stacked and very close to each other. In fact there were a few points with the same value. Looking at the data I could realize the process is stable, operating very close to the median with none crossing specification limits. How can I perform the capability analysis using this data?