Specify the default settings for interval plots

File > Options > Individual Graphs > Interval Plots

Specify default settings for interval plots. The changes you make to the defaults remain until you change them again, even after you exit Minitab.
Type of Interval
  • Standard error: Display standard error bars, which extend one or more standard errors from the mean.
  • Confidence interval: Display confidence intervals. The confidence intervals assume a normal distribution for the data and use t-distribution critical values.
Standard Error Intervals
  • Multiple: Specify a positive number to use as the multiplier for standard errors.
Confidence Intervals
  • Level: Enter a number between 1 and 100 to specify the confidence level. The interval bar end points correspond to the values of a confidence interval for the mean.
  • Bonferroni: Calculate Bonferroni intervals.
Select the location of the bars. For confidence intervals, one-sided bars are shorter than the same side of the two-sided bars because Minitab uses a one-sided test. For standard error bars, the distance the bars extend above or below the mean remains the same, regardless of the side that you specify.
  • two-sided: Draw bars above and below the mean.
  • upper one-sided: Draw bars above the mean.
  • lower one-sided: Draw bars below the mean.
Pool error across groups
Use the pooled degrees of freedom to calculate the critical value from the t-distribution for confidence interval bars. Or use a pooled standard error instead of calculating the error for each subgroup for standard error bars.