Which action is used to reduce sampling error in a study?

Which action is used to reduce sampling error in a study?

• A. Increase sample size
• B. Decrease sample size
• C. Increase measurement error
• D. Increase variability in the population

Answer: (A)

Sampling error is the part of the difference between a sample statistic and the true population parameter that arises simply because you’re looking at a subset, not the whole population. This kind of error shrinks as the sample size grows, because more data points provide a more accurate picture of the population. In most cases, the standard error of a statistic (like the mean) is inversely related to the square root of the sample size, so increasing n reduces the spread of your sample estimates and makes them more precise. Decreasing the sample size would do the opposite and increase sampling error. Increasing measurement error doesn’t reduce sampling variability; it worsens overall error by introducing more noise into each observation. Increasing variability in the population generally makes estimates less precise for a fixed sample size, typically increasing sampling error unless you sample more. So the action that reduces sampling error is to increase the sample size.

Sampling error is the part of the difference between a sample statistic and the true population parameter that arises simply because you’re looking at a subset, not the whole population. This kind of error shrinks as the sample size grows, because more data points provide a more accurate picture of the population. In most cases, the standard error of a statistic (like the mean) is inversely related to the square root of the sample size, so increasing n reduces the spread of your sample estimates and makes them more precise.

Decreasing the sample size would do the opposite and increase sampling error. Increasing measurement error doesn’t reduce sampling variability; it worsens overall error by introducing more noise into each observation. Increasing variability in the population generally makes estimates less precise for a fixed sample size, typically increasing sampling error unless you sample more. So the action that reduces sampling error is to increase the sample size.