In scientific experiments, researchers may manipulate or artificially cause changes in one variable, so that they can investigate how these changes influence the other variables in the study. Variables that influence other variables are called independent variables. Variables that are influenced by other variables are called dependent variables. In the example below, the independent variable is students' stress levels. The dependent variable is students' blood pressure levels.
Read the paragraph and answer the question below.
What does manipulation of variables mean? In some scientific experiments, researchers manipulate or artificially change the levels of the independent variable - the variable that affects the other variables in the study. Then they measure how these changes or manipulations affect the dependent variables. For example, researchers might artificially increase students' stress levels, and then measure their blood pressure. Manipulating stress levels, and then checking that no other variables may also have affected blood pressure, enables the researchers to demonstrate that high stress levels can cause increased blood pressure.
Why do researchers manipulate independent variables in scientific experiments? Choose 1 correct answer.
- manipulate
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