Descriptive Statistics are a branch of statistics used to summarize data and describe patterns in data sets. Descriptive statistics are used to measure central tendency such as the mean or median, to measure spread or variation such as standard deviation or variance, and to quantify the shape of the distribution including skewness or kurtosis. Descriptive statistics provide a good summary of what the data tell us.
Descriptive statistics can be used for both quantitative and categorical data. They are often used to describe populations and the relationships between variables. Descriptive statistics can be used to answer questions such as what is the average income of a particular group or what is the percentage of people in a given country that own a laptop.
The most commonly used descriptive statistics include: mean, median, mode, standard deviation, variance, percentiles, skewness, kurtosis, and range. All of these statistics are useful in summarizing the data, but each has its own unique properties and uses.
Mean is the arithmetic average of a set of numbers and is often used to measure the central tendency of the data. Median is the middle value when the data is arranged in order, while mode is the most frequent item in the data set. Standard deviation is a measure of spread or variation in the data, while range is the full span of the data set. Percentiles are used to divide the data into quartiles or quintiles, for example the 25th percentile is the data point below which 25% of the data falls. Skewness and kurtosis are measures of the symmetry and peakedness of the data, respectively.
Descriptive statistics are an important tool for summarizing data. By providing a good summary of the data, descriptive statistics enable us to gain a better understanding of the data quickly and easily.
