Independent Samples T-Test
Statistically different
A two-sample t-test assess whether the means of two groups are ______________ ______________ from each other.
the null hypothesis should be rejected
As the observed difference between the sample means gets larger, the more confident we become that...
Add the number of participants in each group and subtract 2 df=n1+n2-2
How do you calculate the degrees of freedom for an independent samples t-test?
Relatively equal
If samples come from the same population, what you expect their means to be?
Differences
Rather than looking at relationships between variables, the t-test is interested in looking at ________________ between groups of people/ animals per say.
randomized posttest-only two-group experimental design
The t-test for independents samples analysis method is especially appropriate for....
T-test
This test looks at a bivariate relationship comparing two groups, more specifically two means and is the most simple of statistical tests/ study designs to analyze 'differences'
1. T-test for independent samples 2. T-test for paired samples
What are the two types of two-samples t-tests?
Dependent samples t-test
What is another name for the t-test for paired samples?
Between Groups t-test
What is another word for Independent samples t-test?
A between 2 groups design
What type of design is a T-test for independent samples?
The low-variability case
When comparing the means for the two groups in an independent samples t-test, the two groups appear most different or distinct in which case (title overlap between the two bell-shaped curves)?
When you want to compare the means of two independent groups
When is the t-test for independent samples used?
There is a large enough difference to conclude that there is a mean difference between the populations represented by the groups/ conditions
When you reject the null hypothesis, what can you conclude about the mean difference between the groups/ conditions in the sample?
One can conclude that the mean difference between these groups/ conditions in the sample is not large enough to conclude that there is a mean difference between the populations represented by the groups/ conditions
When you retain the null hypothesis what can you conclude about the mean difference between the groups/ conditions in the sample?
weight each by its degrees of freedom
if you unequal sample sizes, what do you use to get the weighted average of each sample variance?
Homogeneity of Variance
the assumption that samples come from populations with equal variances
group means
the independent samples t-test (between groups t-test) is used to test whether two ________ _______ are different
Pooled variance
when we have unequal sample sizes, we need to get a weighted average of each sample variance
