Chapter 8-Hypothesis Testing Flashcards
Hypothesis Testing
statistical procedure that allows us to use data from a sample to draw inferences about a population
Alpha Level
A probability value used to define the concept of “very unlikely” in a hypothesis test ( the threshold for statistical significance)
What does the alpha level determine?
Risk of Type I Error (false positive)
Critical Regions
Composed of extreme sample values in the tail of distribution that are very unlikely to occur (as defined by the alpha level) if the null hypothesis is true
P value
probability of obtaining a test statistic as extreme or more extreme than that found if H0 is true.
Effect Size
Measure of the absolute magnitude of a difference, effect, or relationship
Effect Size and the Null Hypothesis
The larger the size of the difference, effect, or relationship, the greater the likelihood of rejecting the null hypothesis
Directionality and Null Hypothesis
There is a greater likelihood of rejecting the null hypothesis for a one-tailed test versus a two-tailed test
Alpha value and null hypothesis
The larger the value of , the greater the likelihood of rejecting the null hypothesis
Sample size and null hypothesis
The larger the sample size the greater the probability of being able to detect a difference, effect, or relationship (i.e., rejecting H0)
Two tailed (non-directional) test
he critical region is divided between the two tails of the distribution
Type I Error (False Positive)
Rejecting the null hypothesis when in fact there is no difference, effect, or relationship (i.e., when you should not have rejected it)
Type II Error (False negative)
Failing to reject the null hypothesis when in fact there is a difference, effect, or relationship (i.e., when you should have rejected it)
Statistical Power -reduces the risk of making a type II error
Probability of rejecting the null hypothesis when there is a difference, effect, or relationship (i.e., when you should)
A larger sample produces a small ________ and large ________
standard error and larger z
Larger standard deviation increases the_______ and produces a smaller ________
standard error and smaller z
