Flashcards in 13.2 The t And F Tests Deck (20)
The _-____ is commonly used to examine whether two groups are significantly different from each other.
The _ ____ is a more general statistical test that can be used to ask whether there is a difference among three or more groups or to evaluate the results of factorial designs.
To use the t distribution to evaluate our data, we need to calculate the value of t from the ____ data and evaluate the ____ t in terms of the sampling distribution of t that is based on the null hypothesis.
If the obtained t has a low probability of occurrence (.05 or less), then the null hypothesis is ____.
The t value is a ratio of two aspects of the data, the difference between the group means and the variability within groups.
t = group difference / within-group variability
The group difference is simply the difference between our obtained means; under the null hypothesis, you expect the difference to be zero.
Mean of first group minus mean of second group.
The value of t ____ as the difference between your obtained sample means increases.
The within-group variability is the amount of variability of scores about the ____.
The ____ ____ and the ____ are indicators of how much scores deviate from the group mean.
standard deviation and the variance
When comparing two means, you assume that the ____ of ____ are equal to n1 + n2 - 2, or the total number of participants in the groups minus the number of groups, this is called degrees of freedom.
degrees of freedom
The degrees of freedom are number of scores ____ to ____ once the means are known.
free to vary
A ___-____ test has a specified direction of difference between the two groups. For example, group one will be greater than group two.
A ___-____ test does not specify a predicted direction of difference. For example, group 1 will differ from group 2.
Whether to specify a one-tailed or two-tailed test will depend on whether you originally designed your study to test a ____ hypothesis.
The ____ of ____, or F test, is an extension of the t-test.
analysis of variance
The _ ____ is a ratio of two types of variance: systematic variance and error variance.
____ ____ is the deviation of the group means from the grand mean, or the mean score all individuals and all groups.
____ ____ is the deviation of the individual scores in each group from their respective group means.
The larger the F ratio is, the more likely it is that the results are ____.