t-Tests

Comparing Two Groups
Objectives
Statistical Tests
Hypothesis Testing
Compares groups
Is there sufficIEnt statistical evidence to reject the null hypothesis?
After collecting data, how do we TEST it?
Several different tests
Appropriate test depends on:
Objective
Type of data
Here we will look at tests for variables Output (continuous Y) data with attributes Input (discrete X) data

Example: Two Levels of X
 t-tests

Use t-test when comparing:
Sample mean to another sample mean – 2 Sample
    t-test
Sample mean to a specific value (e.g., target, gOAl, or belIEf) – 1 Sample t-test
Covered in the appendix

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Test is a Signal-to-Noise ratio that compares sample averages to what would be expected if H0 were true
Analyze ROAdmap - 2 Samples
Analyze ROAdmap – Comparing means of two Samples
This is an example of a hypothesis test that compares two sample means.
H0: Bob = Jane
Ha: Bob ≠ Jane
20 samples from each operator