Contents
Why is a paired t-test appropriate?
A paired t-test is used when we are interested in the difference between two variables for the same subject. Often the two variables are separated by time. Since we are ultimately concerned with the difference between two measures in one sample, the paired t-test reduces to the one sample t-test.
What are the main advantages of the paired samples t-test?
Paired t-tests are considered more powerful than unpaired t-tests because using the same participants or item eliminates variation between the samples that could be caused by anything other than what’s being tested.
What is a disadvantage of a paired samples t-test?
Multiple comparisons: T-test cannot be used for multiple comparisons because it results in type I errors. When conducting a paired t-test among a group of samples, it will be difficult to reject the null hypothesis.
What is the difference between a two-sample t test and a paired t test?
Two-sample t-test is used when the data of two samples are statistically independent, while the paired t-test is used when data is in the form of matched pairs. To use the two-sample t-test, we need to assume that the data from both samples are normally distributed and they have the same variances.
What do you need to know about paired samples t test?
For the paired samples t-test, these are independent observations or, more precisely, independent and identically distributed variables; the difference scores between the two variables must be normally distributed in our population.
Which is equivalent to one sample t test?
Technically, a paired samples t-test is equivalent to a one sample t-test on difference scores. It therefore requires the same 2 assumptions.
What is the null hypothesis for a paired sample t-test?
A paired samples t-test always uses the following null hypothesis: Reader Favorites from Statology H0: μ1 = μ2 (the two population means are equal) The alternative hypothesis can be either two-tailed, left-tailed, or right-tailed:
What are the assumptions of a repeated sample t test?
The assumptions underlying the repeated samples t-test are similar to the one-sample t-test but refer to the set of difference scores. 1. The observations are independent of each other 2. The dependent variable is measured on an interval scale 3. The differences are normally distributed in the population.