What are the Independant and dependant variables for a simple Reaction Time lab?

Question

What are the Independant and dependant variables for a simple Reaction Time lab?

Answer 1

In the design of experiments, independent variables are those whose values are controlled or selected by the person experimenting (experimenter) to determine its relationship to an observed phenomenon (the dependent variable). In such an experiment, an attempt is made to find evidence that the values of the independent variable determine the values of the dependent variable (that which is being measured). The independent variable can be changed as required, and its values do not represent a problem requiring explanation in an analysis, but are taken simply as given. The dependent variable on the other hand, usually cannot be directly controlled.

Controlled variables are also important to identify in experiments. They are the variables that are kept constant to prevent their influence on the effect of the independent variable on the dependent. Every experiment has a controlling variable, and it is necessary to not change it, or the results of the experiment won't be valid.

In summary:

The independent variable answers the question "What do I change?".

The dependent variable answers the question "What do I observe?".

The controlled variable answers the question "What do I keep the same?".