From the course: SQL for Exploratory Data Analysis Essential Training
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Exploring data with statistics - PostgreSQL Tutorial
From the course: SQL for Exploratory Data Analysis Essential Training
Exploring data with statistics
- [Instructor] Let's look at exploring data with statistics. Statistics can help us understand characteristics of a data set. A group of statistics known as descriptive statistics provide two kinds of measures. The first is central tendency, which describes different kinds of midpoints in a data set. The other is the spread or variance of data. That describes the range of data and how it is spread out. Central tendency can be measured by the mean, which is also called the average. This is the sum of the values divided by the number of values. For example, the mean of this list is 30. Mode is the data value that occurs most frequently in a set of values. For example, in this list, the mode is 10. The spread of data helps us understand how data is distributed. For example, a bell curve is a common shape of the distribution of data values such as the height of human beings. Sometimes the distribution of data is…