Question

1. In your own words, what is a nonparametric test? What is a parametric test )? 2. In your own words, identify an advantage of using rank correlation instead of linear correlation . 3. In your own words, what is the difference between a nonparametric test and a distribution-free test ?

Answer 1

1. A non-parametric test are known as distribution-free tests and are usually based on fewer assumptions. There is usually no need for key parameters like median or mean etc

b. Parametric tests on the other hand involve estimation of vital parameters like mean or mean deviation etc, and this means that parametric are more powerful than non-parametric tests.

2. While rank correlation coefficient can be used to test and conclude on the direction and strength of a relationship between two variables, linear correlation only evaluates the linear relationship between two continuous variables.

3. Non-parametric tests are usually referred to as distribution-free tests, hence they are the same kind of test.

Explanation: