What statistical techniques are most useful for identifying outliers in samples and in regression analysis? After considering the practical benefits of locating exceptional performers and reviewing a variety of statistical methods for doing so, this paper stresses the merits of several new techniques based on ideas of robust estimation. Although they have the disadvantage of eschewing some traditional and intuitive concepts, these techniques also eschew traditional and unfulfilled assumptions that have often hampered the application of earlier methods to real-life datasets. Throughout the paper, emphasis is given to the use of statistical techniques in the evaluation of public policies, with particular attention to education.
Klitgaard, Robert, Looking for the Best. Santa Monica, CA: RAND Corporation, 1976. https://www.rand.org/pubs/papers/P5598.html. Also available in print form.
Klitgaard, Robert, Looking for the Best, Santa Monica, Calif.: RAND Corporation, P-5598, 1976. As of June 16, 2021: https://www.rand.org/pubs/papers/P5598.html