Estimation Principles

May 26, 2009 Activity webinar presented by Dennis Pearl, The Ohio State Unversity, and hosted by Leigh Slauson, Otterbein College. This webinar describes a computer lab activity using the Flash-based applet at www.causeweb.org/mouse_experiment to teach key principles regarding the value of random assignment. These include: 1) how it helps to eliminate bias when compared with a haphazard assignment process, 2) how it leads to a consistent pattern of results when repeated, and 3) how it makes the question of statistical significance interesting since differences between groups are either from treatment or by the luck of the draw. In this webinar, the activity is demonstrated along with a discussion of goals, context, background materials, class handouts, and assessments.

July 28, 2009 Activity webinar presented by Jo Hardin, Pomona College, and hosted by Leigh Slauson, Otterbein College. Based on an activity by John Spurrier, this webinar uses a baseball example to introduce students to Bayesian estimation. Students use prior information to determine prior distributions which lead to different estimators of the probability of a hit in baseball. The webinar also compares different Bayesian estimators and different frequentist estimators using bias, variability, and mean squared error. The effect that sample size and dispersion of the prior distribution have on the estimator is then illustrated by the activity.

Statistics has been the handmaid of science, and has poured a flood of light upon the dark questions of famine and pestilence, ignorance and crime, disease and death. This is a quote from James A. Garfield, the 20th President of the United States. The quote came in a speech delivered in the House of Representatives on December 16, 1867 in which Garfield (then a congressman) was arguing for the value of a broad and scientifically sound census. The quote is found on page 216 of the 1881 book "The Life and Work of James A. Garfield," by John Clark Ridpath.

Hypotheses like professors, when they are seen not to work any longer in the laboratory, should disappear. This is a quote by British chemist and chemistry education pioneer Henry Edward Armstrong (1848 - 1937). The quote is found in Sir Harold Hartley's chapter on Armstrong in his 1971 book "Studies in the History of Chemistry".