Reliability Results - How Many? Tab

Select the How many? tab of the Reliability Results dialog box to access options to estimate the number of items that would have to be added to the scale in order to attain a particular reliability. The computations will assume that the items that will be added are of approximately equal "quality" as the other items in the scale, that is, that they will be of comparable reliability. The current reliability is displayed in the Current reliability field.

Desired reliability. Enter the desired scale reliability in the Desired reliability box (or use the microscrolls). STATISTICA will compute the number of items that would have to be added to attain that reliability.

How many items? Click the How many items? button to display a spreadsheet containing the current reliability, the desired reliability, and the number of items that must be added in order to achieve the desired reliability.