A
What does ANOVA stand for?
analysis of variance
Can variable x and variable y be interchanged in a regression?
No
What is another word for an negative correlation/relationship?
inverse relationship
What does a positive r squared value mean when interpreting the results of a regression?
As the independent (or predictor variable increases), so does the dependent (or response) variable
What does a correlation of 0 mean?
There is no relationship
As one variable increases, the other stays the same
What do we call the variables in a regression? (we look for the percentage of variance within the _____variable that is explained by the _______ variable)
response and predictor
2. What kind of study establishes causation?
Randomized control experiment
T/F when interpreting the results of a regression analysis, you reject the null hypothesis if the p-value is greater than your significance level
False, If the p-value is greater than your significance level, you don’t reject the null hypothesis
4. What does it mean for a variable to be binary?
it has two levels (e.g., employed or unemployed)
With a negative correlation, as one variable increases the other…
decreases
Which correlation is stronger? -.9 or .65
-.9
Is correlation influenced by sample size?
Yes, small data sets can give you strong correlations just because of the lack of data
What does r squared represent?
The proportion of variance for a dependent variable that is explained by an independent variable
How is the correlation coefficient represented?
r
Why might someone use an ANOVA over a t-test?
They have more than 2 groups
If you are testing whether a single group differs from a known value, which kind of t-test would you use?
one sample t-test
T/F Regression is used for categorical data
False
What kind of variables does a chi squared test work for?
categorical
T/F When interpreting the results of a chi-squared test, you reject the null hypothesis if the test statistic is greater than the critical value
T, If the test statistic is greater than the critical value, we reject the null hypothesis
The significance level is the same as ________?
alpha
What are 3 things you need to establish causation?
That x came before y
That x and y didn’t occur because of chance alone
There is nothing else that accounts for shared relationship
What kind of t-test would you use to test whether two groups differ from each other?
Independent samples
You believe that Bethany students have higher grades than the average college student. What is your null hypothesis (in just words)?
Bethany students' grades are the same as the average college student
Which symbols does the hypotheses of a one-tailed test use?
a. =/
b. >_ <, <_ >
b
How do you calculate degrees of freedom in a t-test?
n-1