Percentiel

Percentiles are a type of quantiles or fractiles that divide the set of observations into a hundred equal parts after arranging the data in ascending order.

Percentiles describe the percentage of data values that fall at or below a particular data point. So, the 50^th percentile has about 50 percent of the data points above and 50 percent below the percentile.

Percentiles are useful for comparing values with larger populations. For example, universities extensively use percentiles to compare students' scores and declare their ranking.

First, arrange all the scores from low to high. Now using the percentile formula, each score can be converted into corresponding percentiles. For instance, if Robert scored 80 marks, what's his percentile score?

First, determine how many students' scores are less than 80. Then divide this number by the total number of students, and multiply this value by 100.

However, a 90^th percentile does not necessarily mean the student has received 90 percent. It means that 90 percent of test scores are lower, and 10 percent are higher than his score.