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    Question

    Which of the following is NOT an effective strategy

    to minimize bias in sampling?
    A Ensuring the sampling frame includes all members of the population Correct Answer Incorrect Answer
    B Using a random number generator to select sample units Correct Answer Incorrect Answer
    C Applying stratified sampling for heterogeneous populations Correct Answer Incorrect Answer
    D Allowing respondents to self-select into the sample Correct Answer Incorrect Answer
    E Increasing the sample size proportionate to the population Correct Answer Incorrect Answer

    Solution

    Explanation: Self-selection introduces significant bias because it relies on individuals' willingness or interest to participate, skewing results toward specific groups and compromising the sample's representativeness. To minimize sampling bias, the selection process must be random, inclusive, and systematic. Ensuring a comprehensive sampling frame, using randomization tools, applying appropriate techniques (e.g., stratified sampling), and adjusting sample sizes help achieve a fair representation of the population, reducing both selection bias and non-response bias. Option A: Ensuring a complete sampling frame reduces undercoverage, ensuring no group is inadvertently excluded. Option B: Random number generators eliminate human error and bias in selection. Option C: Stratified sampling addresses subgroup variability, providing accurate representation in heterogeneous populations. Option E: Larger sample sizes reduce sampling error and increase the reliability of analysis.

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