Mean is a measure of central tendency. In data science, Mean, also termed as the simple average, is an average value of a data set. Basically, mean is a value in the data set around which entire data is spread out. While mean is calculated, all values used in calculating the average are weighted equally.
The mean of a data set is calculated by adding up all the values in the data set and later dividing them by the number of values present in the data frame. Let us understand how to find a mean with the help of below example.
Consider that we have a set of 11 numbers 10 to 20 in a data set.
Array = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20}
So mean is calculated by adding up 10 numbers in the data set.
Sum of all the numbers = 165
Mean = 165/10 = 16.5
Let us now try to understand real life application of mean. We will create a data set for five cities in India for their minimum day temperature on a particular day. Let us record the temperatures in a table.
Following is the sample of data that is collected:
To calculate the mean we will add the temperatures of all cities and divide it by 5.
Mean = (21 + 13 + 24 + 15 + 20)/5 = 18.5° C
Mean in a graph
Mean as represented in the above graph shows it stands for central tendency, meaning, it points to the centre of the data set.
