Selecting Statistics
You assess students’ math anxiety before a course,
teach the course using techniques intended to
reduce this anxiety, and then reassess the same
group of students immediately following the
course.
What is a correlated T test
States that there is no effect, that difference between samples is due to chance
What is the null hypothesis
The probability that the null hypothesis will be rejected if the null hypothesis is false
What is power
Number of scores that are free to vary in calculating that statistic.
What is degrees of freedom
A confidence interval contains zero
What is fail to reject the null hypothesis
You randomly assign 20 students to an
experimental condition and another 20 students
to a control condition.
What is a independent t test
What is a type 1 error
What is the relationship power has with Beta
power - Beta = 1
The magnitude of the real effect
What is cohens d
Significance is the same as importance
What is false
A researcher believes that in recent years women have been getting taller. She knows that 10 years ago the average height of young adult women living in her city was 63 inches. She randomly samples eight young adult women currently residing in her city and measures their heights. The following data are obtained
What is an example of a t test for single samples
When we retain the null hypothesis but the null hypothesis is false
What is a type 2 error
Alpha, N, Size of the real effect
Typical reason we need to use a single-
sample t test rather than a z test?
The sign test ignores ______
What is magnitude
A university president believes that, over the past few years, the average age of students attending his university has changed. To test this hypothesis, an experiment is conducted in which the age of 150 students who have been randomly sampled from the student body is measured. The mean age is 23.5 years. A complete census taken at t he university a few years before the experiment showed a mea n age of 22.4 years, with a standard deviation of 7.6
What is an example of a z test
In a sign test if the null hypothesis is true p real is ____
.50
When you retain the null hypothesis the most plausible interpretation is _____
You might be lacking power
How does power change from a z test to a t test
It gets smaller
The standard deviation of the sampling distribution
Standard Error
What are two assumptions that are the same for all t-tests?
Normally distributed or N greater than or equal to 30
Homogeneity of Variance
research design in which participants are tested two times, resulting in paired scores
Repeated measures design
A study has a small sample size and a small effect size
What is low power
My p value is equal to .01, my alpha is .05
What is reject the null hypothesis
The probability of getting each value under the assumption that it resulted from chance alone
What is a sampling distribution