ENC . BSc 10 Unit Statistics Descriptive Analysis.ppt

Unit Statistics Descriptive Analysis

1. Mean, Median, Mode Mean, Median, Mode
& Range& Range
Prof.Dr.Chinna Chadayan.N
Professor,
Enam Nursing College
Statistics
-Descriptive
Unit 10 Descriptive Analysis 1

2. Matching!
Mean
Range
Mode
Median Middle
Most
Difference
Average
Unit 10 Descriptive Analysis 2

3. Unit 10 Descriptive Analysis
Definition
MeanMean
MeansMeans
AverageAverage
3

4. Mean
•Mean:
–A measure of center, also known as
average.
–Mean is the sum of a set of data
divided by the number of data
items.
Unit 10 Descriptive Analysis 4

5. Unit 10 Descriptive Analysis
Definition
•MeanMean – the average of a
group of numbers.
2, 5, 2, 1, 5
Mean = 3Mean = 3
5

6. Unit 10 Descriptive Analysis
Mean is found by evening
out the numbers
2, 5, 2, 1, 5
6

7. Unit 10 Descriptive Analysis
Mean is found by evening
out the numbers
2, 5, 2, 1, 5
7

8. Unit 10 Descriptive Analysis
Mean is found by evening
out the numbers
2, 5, 2, 1, 5
mean = 3
8

9. Unit 10 Descriptive Analysis
How to Find the Mean of a
Group of Numbers
•Step 1 – Add all the numbers.
8, 10, 12, 18, 22, 26
8+10+12+18+22+26 = 96
9

10. Unit 10 Descriptive Analysis
How to Find the Mean of a
Group of Numbers
•Step 2 – Divide the sum by
the number of addends.
8, 10, 12, 18, 22, 26
8+10+12+18+22+26 = 96
How many addends are there?
10

11. Unit 10 Descriptive Analysis
How to Find the Mean of a
Group of Numbers
•Step 2 – Divide the sum by
the number of addends.
6)96sum# of addends
1
6
36
6
63
11

12. Unit 10 Descriptive Analysis
How to Find the Mean of a
Group of Numbers
The mean or average of these
numbers is 16.
8, 10, 12, 18, 22, 26
12

13. Unit 10 Descriptive Analysis
What is the mean of these
numbers?
7, 10, 16
11
13

14. Unit 10 Descriptive Analysis
What is the mean of these
numbers?
2, 9, 14, 27
13
14

15. Unit 10 Descriptive Analysis
What is the mean of these
numbers?
1, 2, 7, 11, 19
8
15

16. Unit 10 Descriptive Analysis
What is the mean of these
numbers?
26, 33, 41, 52
38
16

17. Unit 10 Descriptive Analysis
Definition
MeMeddianian
is in theis in the
MiMiddddlele
17

18. Median
•Median:
–A measure of center, that tells the middle
number in a set of data.
–If there is no single middle item, the number
halfway between the two data items closest to
the middle is the median.
•Basically…just find the mean of the two
middle numbers.
Unit 10 Descriptive Analysis 18

19. Unit 10 Descriptive Analysis
Definition
•MedianMedian – the middle number
in a set of ordered numbers.
1, 3, 7, 10, 13
Median = 7Median = 7
19

20. Unit 10 Descriptive Analysis
How to Find the Median in a
Group of Numbers
•Step 1 – Arrange the numbers
in order from least to greatest.
21, 18, 24, 19, 27
18, 19, 21, 24, 27
20

21. Unit 10 Descriptive Analysis
How to Find the Median in a
Group of Numbers
•Step 2 – Find the middle
number.
21, 18, 24, 19, 27
18, 19, 21, 24, 27
21

22. Unit 10 Descriptive Analysis
How to Find the Median in a
Group of Numbers
•Step 2 – Find the middle
number.
18, 19, 21, 24, 27
This is your median number.
22

23. Unit 10 Descriptive Analysis
How to Find the Median in a
Group of Numbers
•Step 3 – If there are two middle
numbers, find the mean of these two
numbers.
18, 19, 21, 25, 27, 28
23

24. Unit 10 Descriptive Analysis
How to Find the Median in a
Group of Numbers
•Step 3 – If there are two middle
numbers, find the mean of these two
numbers.
21+ 25 = 46
2)46
23
median
24

25. Unit 10 Descriptive Analysis
What is the median of these
numbers?
16, 10, 7
10
7, 10, 16
25

26. Unit 10 Descriptive Analysis
What is the median of these
numbers?
29, 8, 4, 11, 19
11
4, 8, 11, 19, 29
26

27. Unit 10 Descriptive Analysis
What is the median of these
numbers?
31, 7, 2, 12, 14, 19
13
2, 7, 12, 14, 19, 31
12 + 14 = 262)26
27

28. Unit 10 Descriptive Analysis
What is the median of these
numbers?
53, 5, 81, 67, 25, 78
60
53 + 67 = 1202)120
5, 25, 53, 67, 78, 81
28

29. Unit 10 Descriptive Analysis
Definition
ModeMode
is the mostis the most
PopularPopular
29

30. Mode
•Mode:
–A measure of center for a set of data that tells
the item(s) that appear most often in data set.
–There can be no mode.
–There can also be more than one mode
Unit 10 Descriptive Analysis 30

31. Unit 10 Descriptive Analysis
Definition
•A la modeA la mode – the most
popular or that which is in
fashion.
Baseball caps are a la mode today.
31

32. Unit 10 Descriptive Analysis
Definition
•ModeMode – the number that
appears most frequently in
a set of numbers.
1, 1, 3, 7, 10, 13
Mode = 1Mode = 1
32

33. Unit 10 Descriptive Analysis
How to Find the Mode in a
Group of Numbers
•Step 1 – Arrange the numbers
in order from least to greatest.
21, 18, 24, 19, 18
18, 18, 19, 21, 24
33

34. Unit 10 Descriptive Analysis
How to Find the Mode in a
Group of Numbers
•Step 2 – Find the number
that is repeated the most.
21, 18, 24, 19, 18
18, 18, 19, 21, 24
34

35. Unit 10 Descriptive Analysis
Which number is the mode?
29, 8, 4, 8, 19
8
4, 8, 8, 19, 29
35

36. Unit 10 Descriptive Analysis
Which number is the mode?
1, 2, 2, 9, 9, 4, 9, 10
9
1, 2, 2, 4, 9, 9, 9, 10
36

37. Unit 10 Descriptive Analysis
Which number is the mode?
22, 21, 27, 31, 21, 32
21
21, 21, 22, 27, 31, 32
37

38. Unit 10 Descriptive Analysis
Definition
RangeRange
is the distanceis the distance
BetweenBetween
38

39. Range
•Range:
–A measure of spread.
–The difference (subtraction) between the
greatest data value and least value in a data set.
Unit 10 Descriptive Analysis 39

40. Unit 10 Descriptive Analysis
Definition
•RangeRange – the difference between
the greatest and the least value
in a set of numbers.
1, 1, 3, 7, 10, 13
Range = 12Range = 12
40

41. Unit 10 Descriptive Analysis
How to Find the Range in a
Group of Numbers
•Step 1 – Arrange the numbers
in order from least to greatest.
21, 18, 24, 19, 27
18, 19, 21, 24, 27
41

42. Unit 10 Descriptive Analysis
How to Find the Range in a
Group of Numbers
•Step 2 – Find the lowest and
highest numbers.
21, 18, 24, 19, 27
18, 19, 21, 24, 27
42

43. Unit 10 Descriptive Analysis
How to Find the Range in a
Group of Numbers
•Step 3 – Find the difference
between these 2 numbers.
18, 19, 21, 24, 27
27 – 18 = 9
The range is 9
43

44. Unit 10 Descriptive Analysis
What is the range?
29, 8, 4, 8, 19
29 – 4 = 25
4, 8, 8, 19, 29
44

45. Unit 10 Descriptive Analysis
What is the range?
22, 21, 27, 31, 21, 32
32 – 21 = 11
21, 21, 22, 27, 31, 32
45

46. Unit 10 Descriptive Analysis
What is the range?
31, 8, 3, 11, 19
31 – 3 = 28
3, 8, 11, 19, 31
46

47. Unit 10 Descriptive Analysis
What is the range?
23, 7, 9, 41, 19
41 – 7 = 34
7, 9, 23, 19, 41
47

48. Matching!
Mean
Range
Mode
Median Middle
Most
Difference
Average
Unit 10 Descriptive Analysis 48