Last edited: 2023-09-27
Measures of central tendency
- Mean: the sum of a variable's values divided by the total number of values
- Median: the median is the middle value in a list ordered from smallest to largest
- Mode: the value that occurs most often
Measures of Dispersion and Variability
- Coefficient of Variation: how much variation occurs within your data set. The higher it is the more data points you need to collect to be confident that the sample is representative of the population. It can also be used to compare variation between data sets
- Variance (s²): the expectation of the squared deviation of a random variable from its mean
- Standard Deviation: measure of the amount of variation of a set of values. A low value indicates that the sample tends to be close to the mean, while a high value indicates that the sample is scattered.
- Range: the highest and lowest value in a data set
- Percentile: represent position of a values in data set
- Quartiles: values that divide your data into quarters
- Skewness: measure of the asymmetry of the probability distribution of a real-valued random variable about its mean
- Kurtosis: is a measure of whether the data are heavy-tailed (profusion of outliers) or light-tailed (lack of outliers) relative to a normal distribution
- Correlation: echnique that can show whether and how strongly pairs of variables are related