Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-26T16:18:36.819Z Has data issue: false hasContentIssue false

Transforming a random variable to a prescribed distribution: an application to school-based assessment

Published online by Cambridge University Press:  14 July 2016

Timothy C. Brown*
Affiliation:
Faculty of Science, Frank Fenner Building, Australian National University, Canberra ACT 0200, Australia. Email address: [email protected]

Abstract

When can one find a smooth transformation of a random variable so that the transformed random variable has a specified distribution? If the random variable is continuous, the solution is elementary; if it is discrete, it may be impossible. In this paper, a simple method is given of transforming a random variable in a smooth way to match a specified number of quantiles of an arbitrary distribution. The problem arose from a request for a simple way of transforming marks given in school assessment so that the distribution of transformed marks matches the distribution of external assessment.

Type
Part 5. Properties of random variables
Copyright
Copyright © Applied Probability Trust 2004 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1] Billingsley, P. (1979). Probability and Measure. John Wiley, New York.Google Scholar
[2] Brown, T. C. and Yoon, H. J. (2003) A technical description of statistical moderation in the VCE. Unpublished manuscript.Google Scholar
[3] Daley, D. J. (1995). Scaling formulae for aggregating examination marks. Austral. J. Statist. 37, 253272.CrossRefGoogle Scholar
[4] Daley, D. J. and Seneta, E. (1986). Modelling examination marks. Austral. J. Statist. 28, 143153.CrossRefGoogle Scholar