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That Serbs are more likely to be indicted/sentenced than non Serbs - one tailed.
by vladimir on Mon Mar 16th, 2009 at 09:57:48 AM EST
[ Parent ]
That is not a null hypothesis. The null hypothesis is an unbiased court.

Most economists teach a theoretical framework that has been shown to be fundamentally useless. -- James K. Galbraith
by Migeru (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 09:59:35 AM EST
[ Parent ]
It can be for a t test which can be used to check for a statistically significant difference between the means of two samples.
by vladimir on Mon Mar 16th, 2009 at 11:32:06 AM EST
[ Parent ]
In that case the null hypothesis is the equality of means - that is, lack of bias.

In addition, the t-test requires equality of variances as Jake pointed out. The t-test for equality of means is a sad example of a test that is taught because it can be done in closed form on a blackboard rather than because its conditions actually obtain in real life.

Most economists teach a theoretical framework that has been shown to be fundamentally useless. -- James K. Galbraith

by Migeru (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 12:00:58 PM EST
[ Parent ]
Correct and that's why I calculated the variance of the 2 different data sets.
by vladimir on Mon Mar 16th, 2009 at 12:05:53 PM EST
[ Parent ]
What parameter are you trying to estimate again?

Most economists teach a theoretical framework that has been shown to be fundamentally useless. -- James K. Galbraith
by Migeru (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 12:07:43 PM EST
[ Parent ]
A t test is specific for small sample populations. Why use Poisson?
by vladimir on Mon Mar 16th, 2009 at 11:39:21 AM EST
[ Parent ]
A t test is specific for Gaussian variables.

Most economists teach a theoretical framework that has been shown to be fundamentally useless. -- James K. Galbraith
by Migeru (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 11:58:49 AM EST
[ Parent ]
And why do you assume that the number of indicted or convicted war criminals per number of civilian casualties follow a Gaussian distribution?
by vladimir on Mon Mar 16th, 2009 at 12:04:07 PM EST
[ Parent ]
I don't, that's why I haven't said you should use a t-test.

Most economists teach a theoretical framework that has been shown to be fundamentally useless. -- James K. Galbraith
by Migeru (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 12:08:23 PM EST
[ Parent ]
You could say the number of indicted or convicted war criminals is a Poisson distribution with parameter proportional to the number of civilian casualties, and estimate the coefficient of proportionality.

It is not at all obvious that the ratio of indictees to civilians in that case should follow any given distribution, for instace a Gaussian.

Most economists teach a theoretical framework that has been shown to be fundamentally useless. -- James K. Galbraith

by Migeru (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 12:16:15 PM EST
[ Parent ]
What is the size of the relevant population?

All members of the ethnic group in the whole former Yugoslavia? In the relevant republic? The number of combatants? Or would you expect the number of indictees to be independent of the size of the ethnic group? How about proportionality to the number of dead civilians in other factions, etc?

All this for an unbiased court. You can then quantify the deviations from the model.

Most economists teach a theoretical framework that has been shown to be fundamentally useless. -- James K. Galbraith

by Migeru (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 10:02:57 AM EST
[ Parent ]

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