Hypothesis Tests Of Means Flashcards
What assumption is made when using hypothesis test of means?
In all cases the data are assumed to be random samples from the relevant populations
What is a one-sample t-test used for?
To test whether the mean of an interval scale variable in a sample is consistent with a given value for the mean in the population which is normally distributed.
What assumption is made when using a one-sample t-test?
When the sample size is small the sample must be drawn from a population which is normally distributed.
This can be checked using a histogram of the sample data
What is an independent samples t-test used for?
To test the mean of an interval scale variable in one group is equal to the mean in another group when the two groups are independent
What assumptions are made when using the independent samples t-test?
i) When the size of either of the two random samples is small the variable of interest should be normally distributed in the populations from which the first and second samples came.
This can be checked using histograms of the two populations
ii) The standard deviation in the two populations should be similar.
This can be checked by comparing the two SDs
If the difference in mean of 0 is captured by the 95% CI is the independent samples t-test significant at 5%?
No
If the difference in mean of 0 is not captured by the 95% CI is the independent samples t-test significant at 5%?
Yes
What is a paired samples t-test used for?
To test whether the mean of an interval scale variable in one group is equal to the mean of an interval scale variable in another group when their exists a pairing between the groups
What assumption is made when using paired samples t-test?
When the sample size is small the within pair differences must be drawn from a population which is normally distributed.
This can be checked by using a histogram of within pair differences
