How can precision in measurement be improved?

• A. By decreasing the sample size and increasing variance
• B. By standardizing measurement tools across different populations
• C. By increasing sample size and reducing variance
• D. By minimizing participant involvement during measurement

Answer: (C)

Improving precision in measurement is fundamentally about minimizing errors and variability in the data collected. The correct choice focuses on increasing the sample size and reducing variance.

When the sample size is increased, the data becomes more representative of the population being studied, which helps to capture a broader array of responses and reduces the influence of outliers or anomalies. A larger sample size also leads to more reliable estimates and can result in a tighter confidence interval around a measurement, indicating greater precision.

Reducing variance means minimizing the spread of the data points around the mean. High variance indicates that data points are widely distributed, which can make it harder to discern true trends or effects in the population. By controlling for variables or using more consistent measurement techniques, researchers can achieve lower variance, thereby increasing precision in the results.

This combination of increasing sample size and reducing variance is essential for producing more accurate and dependable data, ultimately leading to more valid conclusions in research studies.