What is an unpaired t-test example?
The unpaired two-samples t-test is used to compare the mean of two independent groups. For example, suppose that we have measured the weight of 100 individuals: 50 women (group A) and 50 men (group B). We want to know if the mean weight of women (mA) is significantly different from that of men (mB).
How does an unpaired t-test work?
The unpaired t test works by comparing the difference between means with the standard error of the difference, computed by combining the standard errors of the two groups. If the data are paired or matched, then you should choose a paired t test instead.
What is unpaired design in research?
Scientific experiments often consist of comparing two or more sets of data. This data is described as unpaired or independent when the sets of data arise from separate individuals or paired when it arises from the same individual at different points in time.
What is t-test used for in research?
A t-test is a type of inferential statistic used to determine if there is a significant difference between the means of two groups, which may be related in certain features.
What is a unpaired t-test?
An unpaired t-test (also known as an independent t-test) is a statistical procedure that compares the averages/means of two independent or unrelated groups to determine if there is a significant difference between the two.
What is the difference between paired and unpaired data?
Paired means that both samples consist of the same test subjects. A paired t-test is equivalent to a one-sample t-test. Unpaired means that both samples consist of distinct test subjects.
What is unpaired test?
Is t-test qualitative or quantitative?
Paired and unpaired t-tests and z-tests are just some of the statistical tests that can be used to test quantitative data. One of the most common statistical tests for qualitative data is the chi-square test (both the goodness of fit test and test of independence ).
What is an unpaired sample?
Unpaired means that both samples consist of distinct test subjects. An unpaired t-test is equivalent to a two-sample t-test. For example, if you wanted to conduct an experiment to see how drinking an energy drink increases heart rate, you could do it two ways.
When to use a paired t test?
The paired t-test is used when the variable is numerical in nature (for example, the height of a person or the weight of a person) and the individuals in the sample are either paired up in some way (such as a husband and wife) or the same people are used twice (for example, preprocedure and postprocedure).
When to use independent sample t test?
The independent-measures t-test (or independent t-test) is used when measures from the two samples being compared do not come in matched pairs. It is used when groups are independent and all people take only one test (typically a post-test).
What are paired t test assumptions?
The paired sample t-test has four main assumptions: • The dependent variable must be continuous (interval/ratio). • The observations are independent of one another. • The dependent variable should be approximately normally distributed. • The dependent variable should not contain any outliers.
What is an example of a paired t test?
The paired sample t-test is also called dependent sample t-test. It’s an univariate test that tests for a significant difference between 2 related variables. An example of this is if you where to collect the blood pressure for an individual before and after some treatment, condition, or time point.