Factor analysis-class 15&16-Group G

Factor analysis: It is the use of one of several methods for reducing a set of variables to a lesser number of new variables, each of which is a function of one or more of the original variables.

To conduct a Factor Analysis, start from the “Analyze” menu.  This procedure is intended to reduce the complexity in a set of data, so we choose “Data Reduction” from the menu.  And the choice in this category is “Factor,” for factor analysis.

Everything you want to get factors for just goes into the list labeled “variables.”  In this case, it’s all the variables. To do a factor analysis, we need to select an “extraction method” and a “rotation method.”  Hit the “Extraction” button to specify your extraction method.

In the dialog box, check the box for a “screen plot.” This will give you a screen diagram which is one way to decide how many factors to extract.

Then, look at the section labeled “Extract.” to decide how many factors to extract.  If you already know exactly how many factors you think there will be, you can set the extraction method to a specific “Number of factors,” and then put the number into this box.

Why factor analysis?

a) Data Summarization

·        Research question is to better understand the interrelationships among the variables

·        Identify latent dimensions within data set

·        Identification and understanding of these underlying dimensions is the goal

b) Data Reduction

·        Discover underlying dimensions to reduce data to fewer variables so all dimensions are represented in subsequent analyses

·        Surrogate variables

·        Aggregated scales

·        Factor Scores

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s   Submitted by:

     Somya Shraddha

      14166

     Group G