ABSTRACT
Statistical procedures are generally performed on numerical data. The numbers involved are derived primarily from the measurement of some characteristic of the subjects in an experiment. The body of knowledge called statistics uses logic and mathematics to help researchers make decisions during and after experiments. The accuracy of measurements depends on their validity and reliability. The validity and reliability of measurement are essential in statistical analysis. Statistics may be descriptive, correlational, or inferential. In some sense, these terms are interchangeable, and they certainly overlap and are related to one another. It is often necessary to consider all three types of statistics in any decision-making process. It includes descriptive statistics, correlational statistics, and inferential statistics. This chapter introduces student to Statistical Package for the Social Sciences, a powerful statistics package that student will use throughout the remainder of the text.
