independent and dependent samples t-tests

what do independent t-tests measure?

measures between two different groups usually comparing two groups on a continuous dependent variable

what is an assumption about independent t-tests

groups are independent

how do you calculate degrees of freedom with two independent variables?

df=(n1-1)+(n2-1)

how do degrees of freedom affect estimates?

more degrees of freedom mean more accurate estimates

how do we usually calculate degrees of freedom?

df= n-1

what does the sp formula provide?

more accurate variability when two group variances are equal

what is a degree of freedom

maximum number of values that can be independent of each other

what do dependent samples t-tests measure?

within group differences

how do alternative hypotheses differ for independent and dependent samples t-tests

independent samples- groups are not equal, dependent samples- groups are one-tailed/directional