Question

Regression/Correlation differs from ANOVA and t-test in what way?  

Answer 1

Correlation: Measuring the strength of a relationship between two continuous variables . In broadest sense correlation is any statistical association , through it commonly refers to the degree to which a pair of variables are linearly related.

Regression: Similar to correlation , but used to define the relationship between two continuous variables such that you can make predictions. e.g. After finding the equation that best describe s the relationship between height and age in the sample, can then predict the height of someone of an age not in your sample.

ANOVA: Compares the means of 3 or more groups. Repeated measures ANOVA is used when it is the same group of people in each group, as in paired t-test.An ANOVA test is a way to find out if survey or experiment results are significant.

There are two main types: one-way and two-way. Two-way tests can be with or without replication.

One-way ANOVA between groups: used when you want to test two groups to see if there’s a difference between them.

Two way ANOVA without replication: used when you have one group and you’re double-testing that same group. For example, you’re testing one set of individuals before and after they take a medication to see if it works or not.

Two way ANOVA with replication: Two groups, and the members of those groups are doing more than one thing. For example, two groups of patients from different hospitals trying two different therapies.

t-test: Compares the means of a variable from two groups. An independent t-test compares the means of two different groups (e.g. Reaction time on a task for man vs women).  Whereas a paired t-test compares the means of the same group at two different times. e.g. - Reaction time for the same people on a task before or after a training period.