Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Winter 5th Sem 3150409 Biostatistics Previous Question Paper
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE- SEMESTER?V (NEW) EXAMINATION ? WINTER 2020
Subject Code:3150409 Date:22/01/2021
Subject Name:Biostatistics
Time:10:30 AM TO 12:30 PM Total Marks: 56
Instructions:
1. Attempt any FOUR questions out of EIGHT questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
4. Notations used in this paper have conventional meaning and need no clarifications.
5. All necessary tables and values are given in this question paper itself
MARKS
Q.1 (a) What is descriptive biostatistics?
03
(b) Explain the terms: geometric mean and harmonic mean.
04
(c)
07
Find the mean from the following data:
Marks (x)
15 5 20 10 20 30 45 25
No. of
5
7 9 10 8
6
3
2
student (f)
Q.2 (a) Calculate the mode for the data given: 100, 97, 110, 200, 75, 120, 150.
03
(b) Calculate mode on the basis of simple frequency distribution of a variable:
04
Variable(x)
1
2
3
4
5
6
7
(Number of bacterial
colonies)
Frequency(f) (Plates)
1
4
12
9
2
1
1
(c) The mean age of 80 students is 16 years and the mean age of another group of 20
07
students is 20 years. Find out the mean age of all the 100-student combined
together.
Q.3 (a) Give the difference between correlation and regression.
03
(b) What is a relation between Mean, Median and Mode?
04
(c) Calculate Mean Deviation:
07
Class Interval 0-4 4-8 8-12 12-16 16-20
Frequency
8 6
4
2
5
Q.4 (a) Write down the assumption of ANOVA.
03
(b) When to use standard deviation and mean deviation?
04
1
(c) Calculate standard deviation of the following data:
07
Class
0-
10-
20-
30-
40-
50-
60-
70-
Interval
10
20
30
40
50
60
70
80
No. of
5
13
20
32
60
80
90
100
fields
,,f
Q.5 (a) Explain Poisson's distribution.
03
(b) A bag contains 4 balls two balls are drawn at random without replacement and
04
found to be white. What is the probability that all balls are white?
(c) Find the correlation between mid term score (x) and final score (y).
07
x 82 81 80 68 70 92 76 80 86 62
y 94 92 85 75 73 95 69 86 90 69
Q.6 (a) Write the assumptions of t-test.
03
(b) Suppose 5% 0f men and 0.25% of women have grey hair. A grey hair person is
04
selected what is the probability that he is a male? Assume equal probabilityfor
men and women.
(c) Find the Rank of correlation between Price and Supply by karl-pearson method.
07
Price
10 12 18 16 15 19 18 17
Supply 30 35 45 44 42 48 47 46
Q.7 (a) What is positive skewness and negative skewness?
03
(b) A sample of 400 male students is found to have a mean height 67.47 inches. Can it
04
be reasonably regarded as a sample from a large population with mean height
67.39 inches and standard deviation 1.30 inches? Test at 5% level significance.
(c) In a certain sample of 2000 families 1400 families consume tea. Out of 1800
07
Hindu families 1236 families consume tea. Use chi square test to find the
association between consumption of tea and family types.
Q.8
Perform LSD for the following data.
14
C 25 B 23 A 20 D 20
A 19 D 19 C 21 B 18
B 19 A 14 D 17 C 20
D 17 C 20 B 21 A 15
***********
2
Selected values of normal distributions
Level of significance Z value- two tailed test Z value- one tailed test
0.10
1.645
1.282
0.05
1.96
1.645
0.02
2.326
2.054
0.01
2.576
2.326
0.001
3.291
3.090
Table : Values of F at the 5% Significance Level
DoF- denominator
DoF- numerator
1
2
3
4
5
6
7
8
9
1
161
200
216
225
230
234
237
239
241
2
18.50
19.00
19.20
19.20
19.30
19.30
19.40
19.40
19.40
3
10.10
9.55
9.28
9.12
9.01
8.94
8.89
8.85
8.81
4
7.71
6.40
6.59
6.39
6.26
6.16
6.09
6.04
6.00
6
5.99
5.14
4.76
4.53
4.39
4.28
4.21
4.15
4.10
8
5.32
4.46
4.07
3.84
3.69
3.58
3.50
3.44
3.39
10
4.96
4.10
3.71
3.48
3.33
3.22
3.14
3.07
3.02
12
4.75
3.89
3.49
3.26
3.11
3.00
2.91
2.85
2.80.
14
4.60
3.74
3.34
3.11
2.96
2.85
2.76
2.70
2.65
16
4.49
3.63
3.24
3.01
2.85
2.74
2.66
2.59
2.54
18
4.41
3.55
3.16
2.93
2.77
2.66
2.58
2.51
2.46
20
4.35
3.49
3.10
2.87
2.71
2.60
2.51
2.45
2.39
30
4.17
3.32
2.92
2.69
2.53
2.42
2.33
2.27
2.21
40
4.08
3.23
2.84
2.61
2.45
2.34
2.25
2.18
2.12
60
4.00
3.15
2.76
2.53
2.37
2.25
2.17
2.10
2.04
Table: Values of F at The 1% Significance Level
DoF-denominator
DoF- numerator
1
2
3
4
5
6
7
8
9
1
4052
5000
5403
5625
5764
5859
5928
5982
6022
2
98.50
99.90
99.20
99.20
99.30
99.30
99.40
99.40
99.40
3
34.10
30.80
29.50
28.70
28.20
27.09
27.70
27.50
27.30
4
21.20
18.00
16.70
16.00
15.50
15.20
15.00
14.80
14.70
6
13.70
10.90
9.78
9.15
8.75
8.47
8.26
8.10
7.98
8
11.30
8.65
7.59
7.01
6.63
6.37
6.18
6.03
5.91
10
10.00
7.56
6.55
5.99
5.64
5.39
5.20
5.06
4.94
12
9.33
6.93
5.95
5.41
5.06
4.82
4.64
4.50
4.39
14
8.86
6.51
5.56
5.04
4.70
4.46
4.28
4.14
4.03
16
8.53
6.23
5.29
4.77
4.44
4.20
4.03
3.89
3.78
3
18
8.29
6.01
5.09
4.58
4.25
4.01
3.84
3.71
3.60
20
8.10
5.85
4.94
4.43
4.10
3.87
3.70
3.56
3.46
30
7.56
5.39
4.51
4.02
3.70
3.47
3.30
3.17
3.07
40
7.31
5.18
4.31
3.83
3.51
3.29
3.12
2.99
2.89
60
7.08
4.98
4.13
3.65
3.34
3.12
2.95
2.82
2.72
4
Table value of "t" at different degrees of freedom on P=0.05 and 0.01 level
P
V
0.05
0.01
1
6.314
31.821
2
2.920
6.965
3
2.353
4.541
4
2.132
3.747
5
2.015
3.365
6
1.943
3.143
7
1.895
2.998
8
1.860
2.896
9
1.833
2.821
10
1.812
2.764
11
1.796
2.718
12
1.782
2.681
13
1.771
2.650
14
1.761
2.624
15
1.753
2.602
16
1.746
2.583
17
1.740
2.567
18
1.734
2.552
19
1.729
2.541
20
1.725
2.528
21
1.721
2.518
22
1.717
2.508
23
1.714
2.500
24
1.711
2.492
25
1.708
.2.485
26
1.706
2.479
27
1.703
2.463
28
1.701
2.467
29
1.699
2.462
30
1.697
2.457
40
1.684
2.423
60
1.671
2.390
120
1.658
2.338
5
Table: Distribution of 2 corresponding to different levels of significance
Probability (P)
Degree of freedom(df)
0.05
0.01
0.001
1
3.84
6.64
10.83
2
5.99
9.21
13.82
3
7.82
11.35
16.27
4
9.49
13.29
18.47
5
11.07
15.09
20.52
6
12.59
16.81
22.46
7
14.07
18.48
24.32
8
15.51
20.09
26.13
9
16.92
21.67
27.88
10
18.31
23.21
29.59
11
19.68
24.73
31.26
12
21.03
26.22
32.91
13
22.36
27.69
34.53
14
23.69
29.14
36.12
15
25.00
30.58
37.70
16
26.30
32.00
39.25
17
27.59
33.41
40.79
18
28.87
34.81
42.31
19
30.14
36.19
43.82
20
31.41
37.57
45.32
21
32.67
38.93
46.80
22
33.92
40.29
48.27
23
35.17
41.64
49.73
24
36.42
42.98
51.18
25
37.65
44.31
52.62
26
38.89
45.64
54.05
27
40.11
46.96
55.48
28
41.34
48.28
56.89
29
42.56
49.59
58.30
30
43.77
50.89
59.70
6
This post was last modified on 04 March 2021