Reading
your Results Report - Correlations
Interpreting
the results of the Correlate function
The
results report for your correlation contains a few pieces
of information that are critical to interpreting your results
report for the Correlate function. There are two different
kinds of results reports, depending on whether or not you
chose to create a correlation matrix of multiple variables,
or a a single correlation coefficient with a scatterplot
graph.
Results Report for Correlating Two Variables
with a Scatterplot
First,
the top row of your results report tells you which two
variables were used in the correlation analysis - it is reported
as Correlation
of (Variable name 1) and (Variable name 2).
You will also see three statistics reported -
the Pearson Correlation coefficient, the N (number of valid
pairs in your data), and the P values (significance level reached).
Next,
take a look at the table that EZAnalyze has created - you
will see that the variable names that you correlated are
along both the top of the table (row 3) and along the side
of the table (column B). To find the correlation coefficient (Glossary),
find the number located at the intersection of row 7 and
column D next to the words Pearson Correlation. The N in
the results report indicates how many cases were used in
computing the correlation, and the P is the significance
level.
You
will also see a scatterplot showing the relationship between
your two variables, and a trendline (line of best fit) if
you selected that option.
Correlation
Matrix Results Report
The correlation matrix results report provides
the Pearson Correlation coefficient, number of valid pairs
of data (N), and the significance level (P) of all possible
correlations between the variables you selected.
RULES
OF THUMB FOR INTERPRETING CORRELATION COEFFICIENTS.
1.
The larger the correlation coefficient, the better.
2. A correlation of less than .3 is typically considered "not meaningful," a
correlation between .3 and .5 is typically considered "weak," a correlation
between .5 and .7 is typically considered "moderate," and a correlation
that is greater than .7 is typically considered to be a strong correlation.
3.
CORRELATION DOES NOT IMPLY CAUSATION. Because two variables
are correlated, even if they are statistically significant,
does not mean that one variable causes changes in the other
- it means nothing more than "they are related."
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