How do experiments work? Let’s do an experiment on the time spent studying and how that changes our ability to remember.
First, we need at least two different settings, called conditions.
We need a condition where people spend only a little time studying, say 30 seconds, and a condition where people spend more time studying, say 5 minutes.
As the experimenters, we are manipulating the time the participants study the lists of words.
The amount of study time is our independent variable. This is the factor that we are interested in, because it might cause a change in our other factor.
Now we need to measure memory.
We do this by asking participants to write down as many words as they remember
and then counting how many words they recall correctly.
We call this memory performance score the dependent variable.
If we find that people recall more words when they have 5 minutes to study than 30 seconds,
then we can say that taking more time to study CAUSED the participants in the 5 minute study condition to recall more words.