Download Descriptive statistics are used to describe the main

Descriptive statistics are used to describe the main features of a collection of data
in quantitative terms. Descriptive statistics are distinguished from inferential statistics (or
inductive statistics), in that descriptive statistics aim to quantitatively summarize a data
set, rather than being used to support inferential statements about the population that the
data are thought to represent. Even when a data analysis draws its main conclusions using
inductive statistical analysis, descriptive statistics are generally presented along with
more formal analyses, to give the audience an overall sense of the data being analyzed.
Descriptive statistics are useful for describing the basic features of data, for example, the
summary statistics for the scale variables and measures of the data. In a research study
with large data, descriptive statistics may help us to manage the data and present it in a
summary table.
One important use of Descriptive Statistics is to summarize a collection of data in a clear
and understandable way. There are two basic methods: numerical and graphical. Using
the numerical approach one might compute statistics such as the mean and standard
deviation. Using the graphical approach one might create a stem and leaf display and a
box plot. Graphical methods are better suited than numerical methods for identifying
patterns in the data. Numerical approaches are more precise and objective.
Types of descriptive statistics
1. Measure of central tendency: In descriptive statistics, the measure of central tendency
measures the average value of the sample. In descriptive statistics, there are two types of
averages: the first are the mathematical averages and the second are the positional
averages.
The mathematical averages are of three types: arithmetic mean, geometric mean, and
harmonic mean. In descriptive statistics, the arithmetic mean is the most widely used
measure for central tendency; it can be obtained by adding all the items of the series and
dividing this total by the number of items. In descriptive statistics, the geometric mean is
defined as the nth root of the products of all the n values of the variable. In descriptive
statistics, the geometric mean is used when the items in the series are very large. The
harmonic mean is defined as the reciprocal of the item. In descriptive statistics, the
harmonic mean is useful in finding the averages that involve speed, time, price and ratio.
There are two types of positional average: the median and the mode. In descriptive
statistics, the median is the average value of the series in which half the values are less
than the median and half the values are greater than the median. The mode, the second
positional average, shows a higher frequency in the series.
2. Measure of dispersion: In descriptive statistics, we can elaborate upon the data further
by measuring the dispersion. In descriptive statistics, usually the range of the standard
deviation and variance is used to measure the dispersion. In descriptive statistics, range is
defined as the difference between the highest and the lowest value. In descriptive
statistics, the standard deviation and variance are usually used to measure the dispersion.
Standard deviation is also called the root mean square deviation. Variance is also used to
measure the dispersion, which can be simply derived from the square of the standard
deviation