# Data Analysis

There are many different ways to analyze high quality data. A few broad analytical categories are described below.

## Descriptive analysis

Descriptive analysis aims to provide a quantitative summary of a data set. In statistical reporting on human subjects, descriptive analysis might include the overall **sample size** and sample sizes of key subgroups. It might include calculations such as **median**, **mean**, and **mode** as measures of **central tendency**, and **standard deviation** as a measure of **variability**.

## Inferential analysis

Inferential analysis is aimed at testing hypotheses about a **population**. In this context, a population isnâ€™t necessarily a group of people; it may be any set of similar objects or events. Statistical methods are used to infer properties of the population based on the sample.

## Qualitative analysis

Qualitative analysis aims primarily at understanding a phenomenon, rather than predicting and testing hypotheses. Examples of qualitative analytical methods include grounded theory analysis and various forms of content analysis, including text mining.