In Systematic Random Sampling from a population of 10,000 using a sample size of 500, the sampling interval 'k' and the starting point are determined. If the randomly selected starting point is 12, the second element selected would be:
- A 32 ✓
- B 22
- C 24
- D 512
Correct answer: A. 32
Explanation
Sampling interval k = N/n = 10,000/500 = 20. Starting point = 12 (randomly selected from 1 to 20). The sample consists of: 12, 12+20=32, 52, 72, ... The second element = 12 + 20 = 32. Systematic random sampling selects every k-th element after a random start. It is more practical than simple random sampling for large populations but can introduce periodicity bias if there is a cyclical pattern in the sampling frame matching the interval k.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.