#### Sampling Techniques and Statistical Inference Book Back Questions

12th Standard EM

Reg.No. :
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Time : 00:45:00 Hrs
Total Marks : 30
5 x 1 = 5
1. A …………. may be finite or infinite according as the number of observations or items in it is finite or infinite.

(a)

Population

(b)

census

(c)

parameter

(d)

none of these

2. A finite subset of statistical individuals in a population is called __________

(a)

a sample

(b)

a population

(c)

universe

(d)

census

3. Any statistical measure computed from sample data is known as ____________

(a)

parameter

(b)

statistic

(c)

infinite measure

(d)

uncountable

4. In simple random sampling from a population of units, the probability of drawing any unit at the first draw is

(a)

$\frac{n}{N}$

(b)

$\frac{1}{N}$

(c)

$\frac{N}{n}$

(d)

1

5. In ___________ the heterogeneous groups are divided into homogeneous groups.

(a)

Non-probability sample

(b)

a simple random sample

(c)

a stratified random sample

(d)

systematic random sample

6. 3 x 2 = 6
7. Explain the stratified random sampling with a suitable example.

8. Explain in detail about sampling error.

9. Explain in detail about non-sampling error.

10. 3 x 3 = 9
11. Using the following Tippett’s random number table,

 2952 6641 3992 9792 7969 5911 3170 5624 4167 9524 1545 1396 7203 5356 1300 2693 2670 7483 3408 2762 3563 1089 6913 7991 0560 5246 1112 6107 6008 8125 4233 8776 2754 9143 1405 9025 7002 6111 8816 6446

Draw a sample of 15 houses from Cauvery Street which has 83 houses in total.

12. Using the following random number table (Kendall-Babington Smith)

 23 15 75 48 59 01 83 72 59 93 76 24 97 08 86 95 23 03 67 44 05 54 55 50 43 10 53 74 35 08 90 61 18 37 44 10 96 22 13 43 14 87 16 03 50 32 40 43 62 23 50 05 10 03 22 11 54 36 08 34 38 97 67 49 51 94 05 17 58 53 78 80 59 01 94 32 42 87 16 95 97 31 26 17 18 99 75 53 08 70 94 25 12 58 41 54 88 21 05 13

Draw a random sample of 10 four- figure numbers startingfrom 1550 to 8000.

13. Find the sample size for the given standard deviation 10 and the standard error with respect of sample mean is 3.

14. 2 x 5 = 10
15. A manufacturer of ball pens claims that a certain pen he manufactures has a mean writing life of 400 pages with a standard deviation of 20 pages. A purchasing agent selects a sample of 100 pens and puts them for test. The mean writing life for the sample was 390 pages. Should the purchasing agent reject the manufactures claim at 1% level?

16. The mean weekly sales of soap bars in departmental stores were 146.3 bars per store. After an advertising campaign the mean weekly sales in 400 stores for a typical week increased to 153.7 and showed a standard deviation of 17.2. Was the advertising campaign successful?