For each of the following examples state the null hypothesis

For each of the following examples, state the null hypothesis and the research hypothesis, in bothe words and symbolic notation:

a. A researcher is interested in studying the relation between teh use of antibacterial products and the dryness of people\'s skin. He thinks these products might alter the moisture in sin compared to other products that are not antibacterial.

b. A student wonders if grades in a class are in a ny way related to where a student sits in the classroom. In kparticular, do students who sit in the front row get better grades, on average, than the general population of students?

c. Cell phones are everywhere, and we are now available by phone almost all of the time. Does this traslate into a change in the nature or closeness of our long-distance relationships?

Solution

A). The null hypothesis would be that the antibacterial products have no affect on the dryness of peoples skin. The null hypothesis is usually rejected or not rejected by chi squared test with (observed- expected)^2/ expected

B. The null hypothesis would be where a student sits does not affect their grade.

C. Cell-phones do not affect our long distance realtionships