ABSTRACT
It has been suggested to the city Education Committee that one school in the city (Old School) has gained a reputation for discouraging girls from studying the sciences. A researcher is commissioned to investigate the matter. The researcher chooses another school in the city (New School) that matches Old School on the range of subjects pupils can choose to study (and also matches Old School on a number of other appropriate factors, such as size, standards, ages taught, ratio of boys to girls, etc. to control for confounding factors). In this city the maximum choice for pupils occurs at the age of fifteen and this is also when the pupils study the widest range of subjects. The researcher randomly selects 20 fifteen year old boys and 20 fifteen year old girls from each school and finds out how many science subjects they have chosen to study. In this experiment there are two independent variables, school and gender, and the dependent variable measured is number of science subjects chosen.
