Research Presentation I made for Summit Consulting giving a high level overview of Linear Discriminant Analysis, with application in Default Modeling (Altman's Z-score)
8. Linear Discriminant Analysis (LDA)
• LDA is a statistical technique used to classify an observation into 1 of
several a priori categorical groups given characteristics vector.
• Common assumptions: X1,…,Xn are normally distributed,
homoscedasticity, identical class covariances
Procedure:
1. Establish group classifications.
2. Collect data for objects in groups.
3. Discriminant coefficient vector determined by “best” maximizing
discrimination between groups.
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14. Robustness through the ages
Original model surveyed only public manufacturing
firms.
Subsequent models estimated coefficient vectors and
new characteristic vectors for private/non-
manufacturing firms as well (Z’ and Z” respectively).
From 1968-1999 model was approximately 80-90%
accurate in predicting bankruptcy 1 year before
event.
Type II error was approximately 15-20%.
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16. Disadvantages
While seemingly effective, Altman’s Z-score has its downsides:
1. Not effective for financial firms.
2. Not significant after 2 years.
3. Financial ratio analysis often fails normality assumption.
4. Cut-offs for groups may alter within a particular industry.
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17. Final Remarks
Altman’s Z-score provides a simple
model to judge financial health.
Great for an initial guess!
Popularized discriminant analysis in
the business field.
Sparked insight into more powerful
statistical financial tools.
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18. References
1. Altman, E. I. Financial Ratios, Discriminant Analysis and the Prediction of
Corporate Bankruptcy. The Journal of Finance, 23, 589-609.
2. Altman, E. PREDICTING FINANCIAL DISTRESS OF COMPANIES:
REVISITING THE Z-SCORE AND ZETA® MODELS . Journal of Finance, 578-
585.
3. Burns, W. (2003). Discriminant Analysis. Applied Statistical Methods ().
4. Waide, J. (Director) (2006, January 25). Discriminant Analysis. Lecture.
Lecture conducted from , Innsbruck.
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