Data - 2 Proportions
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You can have data in two forms: raw or summarized.

Raw data

Raw data can be entered in two ways: stacked and unstacked.

·    Enter both samples in a single column (stacked) with a group column to identify the population. Columns may be numeric, text, or date/time. Events and nonevents are determined by numeric or alphabetical order. Minitab defines the lowest numerical value, or the text value closer to the beginning of the alphabet, as the nonevent; the highest numeric value, or the text value closest to the end of the alphabet, as the event. For example:

-    For the numeric column entries of "5" and "10," observations of 5 are considered nonevents; observations of 10 are considered events.

-    For the text column entries of "agree" and "disagree," observations of agree are considered nonevents; observations of disagree are considered events. If the data entries are "yes" and "no," observations of no are considered nonevents; observations of yes are considered events.

·    Enter each sample (unstacked) in separate numeric or text columns. Both columns must be the same type - numeric or text. Events and nonevents are defined as above for stacked data.

You can reverse the definition of events and nonevents in a text column by applying a value order (see Ordering Text Categories).

The sample sizes do not need to be equal. Minitab automatically omits missing data from the calculations.

Summarized data

Enter the number of trials and the number of events for each sample directly in the 2 Proportions dialog box.