They have been placed on the class website in response to a request by a group of students. Historical research is the interpretation of facts or the finding of patterns.
Problem here is that since subject differ, uncontrolled variable increase.
Trends are identified from using developmental research techniques. This is really the examination of the degree to which variations or differences in one variable are related to variations or differences in the or another viable. They must have equal or the same characteristics. Thus, researcher can look at cause and effect within a system of controlled conditions. Ways to get around problem is to give pre and post tests.