Factor Analysis
Factor Analysis
To measure any of these, we would typically ask many questions that we thought were related to the latent trait, and then factor analyze them to determine the best way to score them, whether all the questions were related to the trait, how many traits there were, and related questions.
There are many types of factor analysis, but they fall into two large groups: Exploratory and confirmatory. In exploratory factor analysis we have no preconceived notions of the factor structure, but in confirmatory we attempt to replicate some earlier results.
There are two phases to factor analysis: extraction of the factors and rotation, and there are a variety of methods for each. The rotations can be divided into orthogonal and oblique methods. In orthogonal factor analysis, we require that each trait (or factor) is orthogonal (uncorrelated) with the other traits. In oblique factor analysis, we do not make this assumption.
Featured Posts

Question: Is the method of determining outliers by flagging data that are more than 3 standard deviations away...

People often transform their variables. There are two sorts of transformation: One is to simply multiply all...

The ttest is a statistical test of whether two sample means (averages) or proportions are equal. It was...

At first, this seems quite simple. Weigh yourself Monday. Weigh yourself next Monday. Did your weight go...

This is a book of recreational mathematics, but it is relatively serious. Several of the chapters have some...

Question: Does lack of correlation imply lack of causation? Answer: We all know that correlation does not...

Modus tollens in logic In logic, there is an argument style called modus tollens: If H0 then R Not R...

I attended the 2015 meeting of the Southeast SAS Users' Group in Savannah, Georgia from September 27  29....

[latexpage] Sometimes we want to compare the spread of a distribution to its mean. This can be useful when we...

PROC LOGISTIC can be used to run logistic regression on a dichotomous dependent variable. Often, these are...

If you picture the data as a 2 x 2 crosstab, then quasicomplete separation occurs when one of the cells is...