Home

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

Testing Whether Jury and Judge Mean Punitive Awards Differ

Finally, one can now test whether the difference between jury and judge punitive awards was likely to occur by chance. That is, just as in the case of 2 x 2 tables, one can ask whether the observed difference was likely to occur by chance.

To calculate the probability that the jury and judge punitive pattern occurred by chance, we need six numbers: mean, standard deviation, and number of observations for both jury and judge punitive awards. All of these numbers appear in Table 2.

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

Use this new handy calculator, and select "Enter mean, SD and N":

Graphpad.com calculators

 

The calculation yields a p-value of just over .10. That is, there is a probability of more than one in ten that we would observe by chance differences this large or larger between mean judge and jury punitive awards if they came from the same population. Hence, the observed difference is not statistically significant.


 
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