Question
Which of the following methods is most effective in
reducing selection bias during the sampling process?Solution
Explanation: Selection bias occurs when certain segments of the population are over- or under-represented in the sample. Stratified sampling effectively combats this issue by dividing the population into well-defined strata and sampling proportionally from each. This ensures balanced representation, minimizes bias, and provides a clearer reflection of the entire population. This technique is particularly useful in diverse populations, where subgroups may have different characteristics relevant to the analysis. Option A: Convenience sampling often increases selection bias as it does not account for representativeness. Option B: Systematic sampling can reduce bias but may inadvertently introduce patterns if the population is ordered. Option D: Self-selection introduces significant bias as it relies on participant interest, skewing the sample. Option E: Historical data may not be representative of current conditions, leading to bias in conclusions.
24, 35, 48, 65, 84, 107
What value should come in the place of (?) in the following number series?
54, 81, 135, 216, 324, ?
8, 12, 20, 32, 52, ?, 136
-1, 5, 23, 59, ?
124, 128, ?, 135, 110, 146
What will come in place of the question mark (?) in the following series?
22, 25, 30, 37, 48, ?
- What will come in place of the question mark (?) in the following series?
3, 10, 29, 66, 127, ? 16, 32, 68, 132, ?, 376
71, 79, 88, 152, ?, 393
- What will come in place of (?) in the given number series.
2, 6, 15, 31, 56, ?