PO218 Lecture Notes - Lecture 2: Statistical Inference, Descriptive Statistics, Common Application
Document Summary
The role of statistics: the role of statistics in the research process, statistical applications, types of variables. Statistical applications: there are two main statistical applications, descriptive statistics: used to describe characteristics of a population or a sample, inferential statistics: used to generalize from a sample to the population from which the sample was drawn. Descriptive statistics: summarize one variable (univariate descriptive statistics include: percentages, averages, and charts and graphs. Example: students have an average gpa of 3. 1) Example: older students tend to have higher gpas than younger students: multivariate descriptive statistics describe the relationships between three or more variables. Example: gpas increase with age for females but not for males. Types of variables: there are many schemes used to classify variables including, independent or dependent variables. Classifying a variable into two or more categories. Rule: do not assign the same numeral to different categories or different numerals to the same category.
