Descriptive and Inferential Statistics

Descriptive and Inferential Statistics

Statistics for psychology defines statistics as formally being "a branch of mathematics that focuses on the organization, analysis, and interpretation of a group of numbers" (Aron, Aron, & Coups, 2009, p 2).  Statistics are a very important component in psychological research because it provides evidence of how likely something will or will not happen through experiments.  In psychology statistics help determine whether or not the theories developed from observations are true or false.  Psychologist use statistical methods to "help them make sense of the numbers they collect when conducting research" (Aron, Aron, & Coups, 2009, p 2).   The two branches of statistical methods used in research by psychologist are descriptive and inferential.  Descriptive statistics are used to summarize and describe a group of numbers from a research study to make the numbers easy to understand. Inferential statistics are used "to draw conclusions and to make inferences that are based on numbers from a research study but go beyond numbers" (Aron, Aron, & Coups, 2009, p 2) . For example, if I was conducting a study to determine if children of single moms were happier than those of single dads.  After collecting data on 100 subjects, I could use descriptive statistics to identify characteristics of the sample, such as the mean happiness levels, ranges of scores and standard deviation; I could use inferential statistics to identify if my sample of data generalizes toward the larger population of children beyond those in my study.

References

Aron, A., Aron, N. E., & Coups, J. E. (2009). Statistics for psychology (5th ed.). Upper Saddle River, NJ: Pearson/Prentice Hall.