The Effect of Prior Probability on Skill in Two-Group Discriminant Analysis

The Effect of Prior Probability on Skill in Two-Group Discriminant Analysis Although the weights in a discriminant function (both linear and quadratic) are independent of group prior probabilities, the performance of the classifier (on the training and validation data) is sensitively dependent on these often unknown probabilities. After reviewing some defects of a popular measure of performance in the situation where the group sizes are naturally disproportionate, three alternative measures of performance (or association) are considered and it is shown that the behavior of the measures as a function of group prior probability is different between measures. Consequently, the optimum choice of the group prior probability depends on the specific measure of performance. Among the measures considered, only two measures - the index of mean square contingency and the Heidke Skill Statistic - are found to be well defined in the disparate-group size situation, and are, therefore, recommended. An empirical data set, dealing with delinquency among high school students is employed to illustrate all of the findings. Quality & Quantity Springer Journals

The Effect of Prior Probability on Skill in Two-Group Discriminant Analysis

Loading next page...
Kluwer Academic Publishers
Copyright © 1998 by Kluwer Academic Publishers
Social Sciences; Methodology of the Social Sciences; Social Sciences, general
Publisher site
See Article on Publisher Site


You’re reading a free preview. Subscribe to read the entire article.

DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

Monthly Plan

  • Read unlimited articles
  • Personalized recommendations
  • No expiration
  • Print 20 pages per month
  • 20% off on PDF purchases
  • Organize your research
  • Get updates on your journals and topic searches


Start Free Trial

14-day Free Trial

Best Deal — 39% off

Annual Plan

  • All the features of the Professional Plan, but for 39% off!
  • Billed annually
  • No expiration
  • For the normal price of 10 articles elsewhere, you get one full year of unlimited access to articles.



billed annually
Start Free Trial

14-day Free Trial