Quantitative psychology is a way of using numbers and statistics to understand human behavior. Imagine you have a bunch of toys and you want to know which ones you like the most. You could just say "I like this one" or "I don't like that one," but that is not very specific.
What if you had a way of giving each toy a score based on things like its color, size, or how fun it is to play with? That's kind of like what quantitative psychology does - it tries to give scores or numbers to different aspects of human behavior so we can understand it better.
For example, let's say we are studying how people feel about going to the dentist. We could ask people to tell us how anxious they feel on a scale of 1 to 10, with 1 being not anxious at all and 10 being extremely anxious. Then we could use the numbers we get from everyone to figure out if certain things, like age or gender, make people more or less anxious.
Overall, quantitative psychology is a way of using numbers and statistics to understand human behavior and figure out how different things, like age or gender, might affect how we think or feel.