Measure of central tendency

Nov 29, 2020

• A measure of central tendency is a summary statistic that represents the center point or typical value of a dataset.
• In other words, it is a central location of a dataset.
• the measure indicates where most values in a distribution falls.
• the three most common central tendency are mean median mode.

Mean

• Mean is average of all the data points also called as arthmetic mean.
• To calculate mean, just add all the data points and divide by the count of numbers.

Copy
datapoints = [5,2,4,1,7,8,3]
x(bar) = (5+2+4+1+7+8+3) / 7 = 4.28

Median

• Median is a middle value in a sorted datapoints.
• We prefer median when we have outliers or skewed data because median are less prone to outliers.
• To calculate median, first - sort the datapoints in ascending ot descending order and pick the middle value.

Copy
datapoints = [5,2,4,1,7,8,3]
sorted = [1,2,3,(4),5,7,8]
median = 4

Copy
datapoints = [20,10,35,25,50,40]
sorted = [10,20,(25,35),40,50]
median = (25+35)/2 = 30

Mode

• Mode is the value which occurs the most frequently in dataset.
• In bar chart, Mode is the highest length bar.
• If your data have multiple values that occuring frequrently, you have a multimodal distribution.
• If no data repeats, then your data do not have a mode.

Copy
datapoints = [10,20,25,50,35,40,40,40,40]
occurance of 40 is 4
Mode = 40

Skewness and Kurtosis and use of Central Tendency >