Manag., December-2019 – Q40
- Option : C
- Explanation : Statistics are numerical characteristics of samples. Parameters are numerical characteristics of populations. When used to estimate a parameter, a statistic is termed an
estimator. Sample statistics are often symbolized by Roman letters, and population parameters are often symbolized by Greek letters.
Good estimators are efficient and unbiased. An efficient estimator requires a minimum of cases to generate a good estimate. An unbiased estimator neither overestimates nor underestimates a parameter. The sample mean ( X ), sample variance (s2), and sample proportion (p) are efficient and unbiased. The sample standard deviation (s) is efficient and has negligible bias.
Point estimates state-specific values. Interval estimates state a range of likely values. Sampling error is the difference between the sample statistic and the population parameter (sampling error = sample statistic – population parameter). A sampling distribution is the distribution of a statistic that results from selecting an infinite number of random samples of the same size from a given population.
