Chapter 6 – Probability and Z-scores for Individual Scores

Now that we have learned how to describe a group of scores with a mean and standard deviation, and also describe where an individual falls within a group of scores with a z-score, we have covered our descriptive statistics, and so it is time to begin our venture into inferential statistics (which is the ultimate focus of this textbook). While descriptive statistics describe a group of scores or an individual’s score, inferential statistics will help us make inferences. These inferences are essentially “educated guesses.” What makes our guesses educated is that they are based on some useful information. Specifically, our inferences are based on probability.