Answer:
Type of investigation = Experimental
Dependent variable = The reaction time of the controllers
Independent variable = Controlled breaks
Explanation:
A researcher is examining the effects of controlled breaks on reaction times of Air Traffic Controllers.
The controllers are randomly assigned to two groups.
Group 1 and Group 2
Group 1 has 20 controllers who spend 45 minutes on a break in a quiet room, with no talking, TV, or other electronics.
Group 2 has 20 controllers who spend their 45 minutes on a break in a common area break room where people are allowed to talk, watch TV, or use electronic devices.
After the breaks, the reaction times of controllers in the two groups were measured.
Type of investigation?
This is clearly an experimental type of investigation where the researcher performs an experiment and after that measures the results.
Type of variables involved?
In this experimental investigation, we have both dependent as well as independent variable.
The controlled break is the independent variable since it can be manipulated by the researcher.
The reaction time of the controllers is the dependent variable since it is being measured and is expected to get affected when the independent variable is manipulated that is controlled breaks.