2.9: Inferential Statistics with Null Hypothesis Testing Flashcards
Null Hypothesis
A statement that assumes there is no effect, difference, or relationship between variables in a study.
What symbol distinguishes the null hypothesis?
H0
What does the null hypothesis serve as?
The baseline assumption that researchers test against.
Null Hypothesis Significance Testing (NHST) Steps
- State the null hypothesis
- Test your hypothesis about variables against a null model
- Express the hypothesis with population parameters
What does the null hypothesis act as?
The starting point for research
What is the p value in a null hypothesis?
p = 0
What is the p value in the alternative hypothesis?
p > 0.05 p<0.05
What is the NHST based on?
The probability of a result if the null hypothesis was true
OR
What is the probability of observing a given result in your data given the null hypothesis was true
What does p indicate?
Probability
What is the typical probability cut off for confidence?
.05
What does the probability cut off indicate?
Whether the null hypothesis will be rejected or not
Alpha Criterion
The threshold probability used to determine whether to reject the null hypothesis
What does p > .05 mean?
There is greater than a 5% chance that no relationship exists in the target population.
What must we do when p > .05?
Fail to reject the null hypothesis
What must we do when p < .05?
Reject the null hypothesis and accept the alternative hypothesis
What is the common starting point in psychological science?
P < .05
Type 1 Error
Rejecting the null hypothesis when the null hypothesis is true.
Type 2 Error
Accepting the null hypothesis when the null hypothesis is false.
What are the two types of statistical inference errors?
- Type 1 error
- Typer 2 error
What is the formula for type 1 error?
a
What is the formula for type 2 error?
B
What is the formula for correctly accepting the null hypothesis?
1 - a
What is the formula for correctly rejecting the null hypothesis?
1 - B
