Probit Analysisoverview how to example data see also
Probit AnalysisStat > Reliability/Survival > Probit Analysis
Use probit analysis when you want to estimate percentiles, survival probabilities, and cumulative failure probabilities for the distribution of a stress, and draw probability plots. When you enter a factor and choose a Weibull, lognormal, or loglogistic distribution, you can also compare the potency of the stress under different conditions.
Minitab calculates the model coefficients using a modified Newton-Raphson algorithm.
Response in event/trial format: Choose if your data is in event/trial format.
Number of events: Enter the column containing the number of events (failures).
Number of trials: Enter the column containing the number of trials.
Response in response/frequency format: Choose if your data is in response/frequency format.
Response: Enter the column that contains the response data.
Frequency (optional): Optionally, enter a column of frequencies.
Stress (stimulus): Enter a column of stress or stimulus levels.
Factor (optional): Enter one column of factor levels.
Assumed distribution: Click the drop-down arrow and choose one of seven common lifetime distributions. Choices include the normal (default), lognormal, logistic, loglogistic, Weibull, and smallest extreme value distributions.