3.2. Estimator and Sampling Distribution#

Learning Outcome

Students will be able to estimate the parameters of a model, use simulation methods to evaluate different estimators, and describe their bias and variance.

Sample Tasks

  • Identify the parameters of a statistical model to be estimated.

  • Compute one-sample summaries (estimates) of the center of a distribution – mean, median, and trimmed mean.

  • Simulate samples of data from a generative model, summarize the sample with an estimator, and examine the estimator’s sampling distribution (histogram / density estimate), its center and its spread.

  • Use the center and spread of the sampling distribution to describe the accuracy of an estimator in terms of bias and variance.

  • Simulate data to explore and evaluate sampling distributions of estimators in complex statistical models.

[OhioDoHEducation21]

Our first readings, from Computational and Inferential Thinking [ADW21], discusses the parameter(s) of a distribution and estimating these parameters with a statistic (or several statistics).

Reading Questions

  • What is the difference between a parameter and a statistic?

  • What is the difference between the distribution of a population and the distribution of a statistic?

Our second readings, also from Computational and Inferential Thinking [ADW21], go deeply into estimating two statistics: the mean and the standard deviation.

Reading Questions

  • When will the mean equal the median?

  • What does the standard deviation tell about how spread out the data is?

  • What is the difference between the standard deviation of the data and the standard deviation of sample means?

  • Is the sample mean a biased or unbiased estimator of the population mean?