This presentation is about measures central tendency.

1. Presented by Zakira Khan

2.  In general terms, central tendency is a
statistical measure that determines a single
value that accurately describes the center of
the distribution and represents the entire
distribution of scores.
 The goal of central tendency is to identify
the single value that is the best
representative for the entire set of data.

3.  Thus we can say that the central tendency is
very important for initial data analysis and
we can use it in the following ways.
 To find representative data.
 To make more concise data.
 To make comparisons.
 Helpful in further statistical analysis.

4. There are three measures of central tendency
which are commonly used.
 1. Mean
 2. Median
 3. Mode

5.  The mean is the most commonly used
measure of central tendency.
 The mean is obtained by computing the sum,
or total, for the entire set of scores, then
dividing this sum by the number of scores.
 This is also called average.
 It is represented by X bar.

6.  Example for Mean:
Find the mean of the following set of Data.
2,4,6,7,3,9,12
Thus Mean = 43/7 = 6.14

7. Now some examples of mean from our daily
life.
 It helps teachers to see the average marks of
the students.
 To calculate the average speed of any thing.
 To calculate the average number of patients
on daily basis.
 To find the average height of students in a
class. etc

8.  If the scores in a distribution are listed in order
from smallest to largest, the median is defined
as the midpoint of the list.
 The median divides the scores so that 50% of the
scores in the distribution have values that are
equal to or less than the median.

9.  If the distribution has odd number of scores,
the median is the middle one after arranging
them in order. For example
2,3,4,6,7,9,12
Median is 6.

10.  If the distribution has even number of scores,
the median is the average of middle two
numbers after arranging them in order. For
example.
2,3,4,5,6,7,8,9
Average = (5+6)/2
= 5.5
Thus median is 5.5.

11. Some examples of median from daily life.
 To find the middle age from the class
students.
 It is used to measure the distribution of the
earnings.
 Used to find the middle height of football
players. etc

12.  The mode is defined as the most frequently
occurring category or score in the distribution.
 In a frequency distribution graph, the mode is
the category or score corresponding to the peak
or high point of the distribution.
 Example
2,3,3,4,5,6,6,6,7,9,12
Here the mode is 6.

13. Some examples of mode from daily life.
 To find which mobile network is used most.
 To find which medium of transport is used by
public. etc

14.  Find the mean, median and mode from the
following data sets and compare them.
Set A= 2,3,3,4,5,8,9
Set B= 2,3,5,3,6,8,10
Mean=
Median=
Mode=