Factor Analysis
C8057 (Research Methods II): Factor Analysis on SPSS
Factor Analysis Using SPSS
The theory of factor analysis was described in your lecture, or read Field (2005) Chapter 15.
Example
Factor analysis is frequently used to develop questionnaires: after all if you want to measure an ability or trait, you need to ensure that the questions asked relate to the construct that you intend to measure. I have noticed that a lot of students become very stressed about SPSS.
Therefore I wanted to design a questionnaire to measure a trait that I termed ‘SPSS anxiety’. I decided to devise a questionnaire to measure various aspects of students’ anxiety towards learning SPSS. I generated questions based on interviews with anxious and non-anxious students and came up with 23 possible questions to include. Each question was a statement followed by a five-point Likert scale ranging from ‘strongly disagree’ through ‘neither agree or disagree’ to ‘strongly agree’. The questionnaire is printed in Field (2005, p. 639).
The questionnaire was designed to predict how anxious a given individual would be about learning how to use SPSS. What’s more, I wanted to know whether anxiety about SPSS could be broken down into specific forms of anxiety. So, in other words, are there other traits that might contribute to anxiety about SPSS? With a little help from a few lecturer friends I collected 2571 completed questionnaires (at this point it should become apparent that this example is fictitious!). The data are stored in the file SAQ.sav.
Questionnaires are made up of multiple items each of which elicits a response from the same person. As such, it is a repeated measures design.
Given we know that repeated measures go in different columns, different questions on a questionnaire should each have their own column in SPSS.
Initial Considerations
Sample Size
Correlation coefficients fluctuate from sample to sample, much more so in small samples than in large. Therefore, the
Factor Analysis Using SPSS
The theory of factor analysis was described in your lecture, or read Field (2005) Chapter 15.
Example
Factor analysis is frequently used to develop questionnaires: after all if you want to measure an ability or trait, you need to ensure that the questions asked relate to the construct that you intend to measure. I have noticed that a lot of students become very stressed about SPSS.
Therefore I wanted to design a questionnaire to measure a trait that I termed ‘SPSS anxiety’. I decided to devise a questionnaire to measure various aspects of students’ anxiety towards learning SPSS. I generated questions based on interviews with anxious and non-anxious students and came up with 23 possible questions to include. Each question was a statement followed by a five-point Likert scale ranging from ‘strongly disagree’ through ‘neither agree or disagree’ to ‘strongly agree’. The questionnaire is printed in Field (2005, p. 639).
The questionnaire was designed to predict how anxious a given individual would be about learning how to use SPSS. What’s more, I wanted to know whether anxiety about SPSS could be broken down into specific forms of anxiety. So, in other words, are there other traits that might contribute to anxiety about SPSS? With a little help from a few lecturer friends I collected 2571 completed questionnaires (at this point it should become apparent that this example is fictitious!). The data are stored in the file SAQ.sav.
Questionnaires are made up of multiple items each of which elicits a response from the same person. As such, it is a repeated measures design.
Given we know that repeated measures go in different columns, different questions on a questionnaire should each have their own column in SPSS.
Initial Considerations
Sample Size
Correlation coefficients fluctuate from sample to sample, much more so in small samples than in large. Therefore, the