26.42 Types of statistics and statistical tests

26.42.1 Descriptive statistics

  • Descriptive statistics are used to summarize data in a few numbers, such as the mean and SD
  • Often the goal of statistics is inference, to learn something about the properties of the population from the sample
  • Statistics are also useful for hypothesis testing
  • Statistics are relevant to either or distributions
  • are relevant to normal (bell-curve) distributions, and apply when the distribution is not normal or unknown
  • The most common statistics compare two variables. However, sophisticated procedures exist for analyzing the relationships among many variables simultaneously
  • Methods exist for comparing matched samples, samples that correspond value by value rather than just as a whole group