Principal Components and Factor Analysis

Ribbon bar. Select the Statistics tab. In the Advanced/Multivariate group, click Mult/Exploratory and from the menu, select Factor to display the Factor Analysis Startup Panel.

Classic menus. From the Statistics - Multivariate Exploratory Techniques menu, select Factor Analysis to display the Factor Analysis Startup Panel.

The Startup Panel contains one tab: Quick.

See also the Factor Analysis Index, Overviews, and Example.

Variables. Click the Variables button to display a standard variable selection dialog box. Select all variables that are to be included in the factor analysis.

Input file. There are two selections in the Input file option: Raw Data and Correlation Matrix.

Raw Data. If you select Raw Data, STATISTICA expects a standard raw data file as input.

Correlation Matrix. If you select Correlation Matrix, STATISTICA expects a correlation matrix as input. Correlation matrix files can be created from within Factor Analysis or another STATISTICA module (e.g., Basic Statistics, Canonical Analysis, Multiple Regression, etc.). Correlation matrix files can also be created directly via the Create New Document - Spreadsheet tab (see also, Matrix file format). Note that if your Input File consists of correlation coefficients only (e.g., from a published source), and no means, standard deviations, or N is available, you can assume standardized data (mean = 0, standard deviation = 1) and an N of, for example, 100 (N must be greater than the number of variables in the analysis). You will first need to add these four cases (means, standard deviation, cases, and matrix) to your spreadsheet before you can run the analysis. Of course, in the results, the descriptive statistics for each variable are not meaningful in that case, however, the factor analysis can be performed based on the correlation coefficients alone.

OK. Click the OK button to display either the standard variable selection dialog box or the Define Method of Factor Extraction dialog box (if variables have already been selected.)

Cancel. Click the Cancel button to close the Startup Panel without performing an analysis.

Options. See Options Menu for descriptions of the commands on this menu.

Open Data. Click the Open Data button to display the Select Data Source dialog box, which is used to choose the spreadsheet on which to perform the analysis. The Select Data Source dialog box contains a list of the spreadsheets that are currently active.

Select Cases. Click the Select Cases button to display the Analysis/Graph Case Selection Conditions dialog box, which is used to create conditions for which cases will be included (or excluded) in the current analysis. More information is available in the case selection conditions overview, syntax summary, and dialog box description.

W. Click the W (Weight) button to display the Analysis/Graph Case Weights dialog box, which is used to adjust the contribution of individual cases to the outcome of the current analysis by "weighting" those cases in proportion to the values of a selected variable.

MD deletion. The MD deletion options are only active if Raw Data has been specified as the Input file (see Factor Analysis Startup Panel - Quick tab). Missing data (MD) can be deleted Casewise, Pairwise, or by Mean Substitution depending on the option specified here.

Casewise. If this option button is selected, only cases that do not contain any missing data for any of the variables selected for the analysis will be included in the analysis.

Pairwise. If this option button is selected, cases will be excluded from the calculation of correlations involving variables for which they have missing data. In subsequent analyses, all tests of statistical significance in that instance will be based on the smallest number of valid cases found in any of the selected variables.

Mean substitution. If this option button is selected, missing data will be replaced by the means for the respective variables (for this analysis only, not in the data file).