In this section we show you how to analyse your data using a pearson s correlation in stata when the four assumptions in the previous section assumptions have not been violated you can carry out a pearson s correlation using code or stata s graphical user interface gui after you have carried out your analysis we show you how to interpret your results.
How to read correlation matrix stata.
When you need the matrix stored as a stata matrix so that you can further manipulate it.
A correlation matrix conveniently summarizes a dataset.
I told her to trust me when i said she really really really needed to read the handout.
In practice a correlation matrix is commonly used for three reasons.
In statistics the correlation coefficient r measures the strength and direction of a linear relationship between two variables on a scatterplot.
When to use a correlation matrix.
This tutorial explains how to find all three types of correlations in stata.
Correlation analysis is conducted to examine the relationship between dependent and independent variables.
We use this 0 1 variable to show that it is valid to use such a variable in a.
The variable female is a 0 1 variable coded 1 if the student was female and 0 otherwise.
I told her to read my handout on how stata creates simulated data from a correlation matrix.
And sometimes a correlation matrix will be colored in like a heat map to make the correlation coefficients even easier to read.
Matrix accum r varlist noconstant deviations.
To interpret its value see which of the following values your correlation r is closest to.
The correlate command will report the correlation matrix of the data but there are occasions when you need the matrix stored as a stata matrix so you can further manipulate it.
We have used the hsb2 data set for this example.
Matrix accum r varlist nocons dev.
Matrix r corr r the first line places the cross product matrix of the data in r the second line converts that to a correlation matrix.
She said she already understood how stata worked but she didn t understand why race had values like 471 583 etc.
After that she finally got it.
The second line converts that to a correlation matrix.
Matrix r corr r the first line places the cross product matrix of the data in matrix r.
The variables read write math and science are scores that 200 students received on these tests.
You can obtain the matrix by typing.
Stata test procedure in stata.
Used when you wish to use spearman correlation but the sample size is small and there are many tied ranks.
Pairwise correlation which treat each pair of variables separately and only includes observations which have valid values for each pair in the data set.
The value of r is always between 1 and 1.
This page shows an example of a correlation with footnotes explaining the output.
