1) The document is a final exam for veterinary medicine students containing 14 multiple choice and written response questions about statistics. 2) The exam covers topics like different sampling methods, probability distributions, correlation, and linear regression. 3) It provides a sample size calculation question using stratified random sampling and asks students to compute the expected value, variance, correlation coefficient, slope, and intercept from provided data and interpret the results.

1. 1
Wolaita Sodo University
College of natural &computational sciences
Department of statistics
Introduction to Statistics Final examination for Vet. Medicine year Students
Name:
ID.No:
Section:
==== General Instruction ====
1. Switch off your cellphone.
2. This examination paper contains 14 questions.
3. Write your Answer or Solution on the space provided.
Max.value: 40%
Feburary 2022
Duration 1:30
Set by : Hailemichael M.

2. 2
ID.NO:
Part I: Choose the best answer from the given alternatives (1.5 PT)
1. A method of sampling in which every Kth member in the total population is chosen for
inclusion in the sample after the first member of the sample is selected at random is
A. Systematic random sampling C. Stratified random sampling
B. Simple random sampling D. Cluster random sampling
2. A method of sampling in which a sample obtained by dividing a heterogeneous population
in to sub groups and drawing from each subgroup is
A. Simple random sampling C. Systematic random sampling
B. Stratified random sampling D. Cluster random sampling
3. A university has 2000 male and 500 female faculty members. The Human Resources de-
partment is commissioning a survey on childcare, and wants to sample 100 faculty members.
What kind of sampling method would best represent the possibly differing opinions of males
and females ?
A. Simple random sampling C. Systematic random sampling
B. Stratified random sampling D. Multistage random sampling
4. In how many different ways can a flag of three colors be formed from 8 different colors ?
A. 11 B. 336 C. 56 D. 24
5. A set containing all possible outcomes of a random experiment is .........
A. Outcome C. Experiment
B. Sample space D. Elementary event
6. One of the following considers order?
A. Permutation C. Multiplication
B. Combination D. All

3. 3
ID.NO:
7. In tossing two coins the sample space is.
A. S = {HT, T H} C. S = {HH, HT, T T }
B. S = {H, T } D. S = {HH, T H, HT, T T }
8. For binomial distribution, with n and p, the mean is
A. n x p B. n x p x q C. 2 x p D. λ
9. The distribution having the same mean and variance is.......
A. Poisson B. Binom ial C. Normal D. Uniform
10. A measure used to determine strength and direction of liner relation between two variable is----
A. Variance C. Slope
B. Correlation coefficient D. Standard error
Correlation coefficient values is always takes-----.
A. Between 0 and 1 B. Between -1 and 0 C. Less than 1 D. Greater than 0
Five families are to be selected from a list of fifty families by systematic random sampling. If
the first member is 7, then the next one is------.
A. 10 B. 12 C. 17 22
Answer key for part I: 18 PTS
10. ..............
11. ..............
12. ..............
11
.
7. ..............
8. ..............
9. ..............
1. .............. 4. ..............
2. .............. 5. ..............
3. .............. 6. ..............
12
.

4. 4
ID.NO:
Part II: Writing (22PTs)
13. Write at list 4 uses of sampling (2pts)
14. What is the difference between discrete and continuous probability distribution? (2pts)
15. Let the probability distribution of random variable X be given in table below.Find E(X) & Variance(X) (4pts)
X = x 0 1 2 3
P (X = x) 0.1 0.2 0.3 0.4
[Solution:]
E(X) Variance(X)
16. Suppose you are a Vet epidemiologist for the county cooperative. You want to know the rela-
tionship between cows’ food intake : X (measured in lb.) and milk yield: Y(measured in lb.)?
You gather the data and obtain summary values as:
n = 5, ∑ Xi = 45, ∑Yi = 30, ∑Xi
2 = 469, ∑Yi
2 = 229, ∑ (Xi × Yi) = 324.4
(a) Compute r, and interpret your result. (4 pts)
(b) Compute β0, β1. (4 pts)
(c) What you expect milk yield be if cow food intake to be 5 lb. ? interpret. (2 pts)
(d) What is the dependent and independent variable (2 pts)
ˆ ˆ

5. 5
[Solution:]