TOPIC 10: Measure of central tendency

MEASURE OF CENTRAL TENDACY

Measure of central tendency can be the term which defines the centre of data. Measures of central tendency are the mean, mode, median, and standard deviation of a set of data.

There are 3 of measure of central Tendacy .

1. Mean
2. Median
3. Mode

 

Definition Mean:
Mean of data is a set of numerical values is the arithmetic average of the data values in the set. It is found by adding all the values in the data set and dividing the sum by the total number of values in the set.

Definition Median:
For an ordered data set, median is the value in the middle of the data distribution. If there are even number of data values in the set, then there will be two middle values and the median is the average of these two middle values.

Definition Mode Mode is the most frequently occurring value in the data set.

In addition to these three important measures of central tendency, another measure is also defined.

Examples

1) Mean.

3, -7, 5, 13, -2

• The sim of these number is 3 -7 + 5 + 13 - 2 =12
• There are 5 numbers
• The mean is equal to 12 ➗ 5 = 2.4

  The mean of the above numbers is 2.4

here is how to do it one line:

mean = 3 - 7 + 5 + 13 - 2 ➗ 5 = 12 / 5 = 2.4



2) Median

How to find the median value?

Solution: Put them in order:

 3, 5, 12

The middle is 5, so the median is 5.

 

 

3) Mode

 

{19, 8, 29, 35, 19, 28, 15}

 

Arrange them in order: {8, 15, 19, 19, 28, 29, 35}

19 appears twice, all the rest appear only once, so 19 is the mode.

This are the 3 question to try.

 

1) What is the mode for the numbers 7, 6, 5, 8, 7, 5, 9, 3, 5, 4?

 

2) What is the median of the following numbers? 9,8,1,8,5?

 

3) What is the mean of the numbers 8, 9, 13 and 18?