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Section 3:
Means and Medians
Trial Award Patterns
Probability
Standard Deviation
Normal Distributions
Logarithms
Awards Test
 

Logarithms

Transforming the data

One can test whether data are normally distributed, and the test shows that the compensatory and punitive awards in Table 1 are not normally distributed. This lack of normality is common in real-world data involving dollar amounts. Because some useful statistical tests depend on the data being normally distributed, or at least symetrically distributed, it is common to transform the data to obtain a distribution that more closely approximates a normal distribution.

One common transformation is to take the logarithm of the original value. That is, we can replace the value of each punitive award with the logarithm of the punitive award, and replace the value of each compensatory award with the logarithm of the compensatory award.

Table 2 reports the transformed variables, now in logarithms, that appeared in Table 1.

Table 2. Jury and Judge Trial Award Patterns
(in log dollars)

 
Mean
Number of Plaintiff Awards
Standard Deviation
 
Jury
Judge
Jury
Judge
Jury
Judge
Compensatory damages
4.70
4.36
3,001
1,375
0.891
0.808
Punitive damages
4.66
4.36
121
55
1.241
1.044

The awards reported in Table 2 are in base 10 logarithms. Therefore, an award of 4.0 corresponds to an award of 10 to the fourth power or 104, or $10,000. An award of 6.0 corresponds to an award of 106, or $1 million.


 
Copyright © 2002 by Theodore Eisenberg & Kevin M. Clermont
Cornell University
Cornell Law School
Cornell University
Comments to ted@teddy.law.cornell.edu
Last updated: September 2002