Correlations Flashcards
A correlation assesses
The degree to which two variables co-relate
Correlation coefficient (r) provides
Index of the extent to which two variables are linearly correlated
What values do we look at in the output for a Pearson’s correlation?
R (the correlation)
Sig. (P)
N
Degrees of freedom is calculated by
N - 2
Pearson’s correlated makes two assumptions
- Variables measured on continuous scale
2. Variables are linearly related
If Pearson’s assumptions are violated, a ____________ should be used
Non-parametric correlation
If Pearson’s assumptions are violated, a non-parametric correlation should be used which uses
Ranked scores
Example of a non-parametric correlation
Spearman’s Rho
A correlation can tell us the ______ of the relationship between two variables
Strength
The coefficient is denoted as _
R
Correlation values can range from ___ to ___
-1 to +1
In the table for partial correlations, the df are listed, so do not…
Take 2 off the value
How many degrees of freedom do you report for a correlation? 1 or 2
1
How do you calculate degrees of freedom for a standard Pearson’s correlation?
N-2
How do you calculate degrees of freedom for a partial correlation?
N (do not take any away)
