PPT - Sampling Theory - 2 | SSC CGL Tier 2 - Study Material, Online Tests, Previous Year PDF Download

 Page 1


CPT Section D Quantitative Aptitude Chapter 15 
Prof. Bharat Koshti 
 
Page 2


CPT Section D Quantitative Aptitude Chapter 15 
Prof. Bharat Koshti 
 
Different Methods of Sampling 
• 1. Probability Sampling Methods 
• 2. Non-Probabilistic Sampling Methods 
• 3. Mixed Sampling Methods 
Page 3


CPT Section D Quantitative Aptitude Chapter 15 
Prof. Bharat Koshti 
 
Different Methods of Sampling 
• 1. Probability Sampling Methods 
• 2. Non-Probabilistic Sampling Methods 
• 3. Mixed Sampling Methods 
(1) Probability Sampling Methods 
In this method there is a fixed/ pre-assigned Probability 
for each member to be selected in the sample from the 
population. 
(a) Simple Random Sampling(SRS): In this method 
there is an equal chance/probability for every member 
being selected in the sample.  
Page 4


CPT Section D Quantitative Aptitude Chapter 15 
Prof. Bharat Koshti 
 
Different Methods of Sampling 
• 1. Probability Sampling Methods 
• 2. Non-Probabilistic Sampling Methods 
• 3. Mixed Sampling Methods 
(1) Probability Sampling Methods 
In this method there is a fixed/ pre-assigned Probability 
for each member to be selected in the sample from the 
population. 
(a) Simple Random Sampling(SRS): In this method 
there is an equal chance/probability for every member 
being selected in the sample.  
There are two methods in Simple Random Sampling- 
One Simple Random Sampling With replacement (SRSWR)& 
another is Simple Random Sampling without 
replacement(SRSWOR). 
Simple Random sampling is useful when- 
(i) The population size is not very large. 
(ii) The population under study is not heterogeneous. 
Page 5


CPT Section D Quantitative Aptitude Chapter 15 
Prof. Bharat Koshti 
 
Different Methods of Sampling 
• 1. Probability Sampling Methods 
• 2. Non-Probabilistic Sampling Methods 
• 3. Mixed Sampling Methods 
(1) Probability Sampling Methods 
In this method there is a fixed/ pre-assigned Probability 
for each member to be selected in the sample from the 
population. 
(a) Simple Random Sampling(SRS): In this method 
there is an equal chance/probability for every member 
being selected in the sample.  
There are two methods in Simple Random Sampling- 
One Simple Random Sampling With replacement (SRSWR)& 
another is Simple Random Sampling without 
replacement(SRSWOR). 
Simple Random sampling is useful when- 
(i) The population size is not very large. 
(ii) The population under study is not heterogeneous. 
5.5 
Person 
Das 
 
0.87487 
Tripathi 0.89068 
Joshi 0.11597 
   Agarwal 0.58635 
Shah  0.34346 
   Purohit 0.24662 
Singhal 
 
0.47609 
     Bhandari 0.08350 
    Kulkarni 0.53542 
Arora  0.37239 
  Gupta 
 
0.73809 
Generate  
Random # 
Person 
1     Bhandari 0.08350 
2 Joshi 0.11597 
3      Purohit  0.24662 
4 Shah  0.34346 
5 
Arora  
0.37239 
Singhal 
 
0.47609 
   Kulkarni 0.53542 
     Agarwal 
0.58635 
Gupta 0.73809 
Das 0.87487 
Tripathi 0.89068 
Sorted  
Random # 
A government income tax auditor wants to 
choose a sample of 5 out of 11 IT returns to 
audit