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    Question

    A researcher collects multiple random samples from a

    population and calculates the sample means. He notices that the means vary across different samples. What is the primary reason for this variation?
    A Measurement errors in data collection Correct Answer Incorrect Answer
    B Sampling variation due to random chance Correct Answer Incorrect Answer
    C Incorrect data preprocessing Correct Answer Incorrect Answer
    D Bias introduced by the researcher Correct Answer Incorrect Answer
    E Inadequate sample size Correct Answer Incorrect Answer

    Solution

    Explanation:- Sampling variation refers to the natural fluctuation in sample statistics (e.g., sample mean) when different random samples are drawn from the same population. Even if the sampling method is unbiased, each sample is slightly different , leading to variations in estimates. This happens because random samples may include different observations from the population, causing sample means to differ. The larger the sample size, the lower the sampling variation, as the sample better represents the population.  

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