A Statistical Analysis of the ICTY's bias. | 220 comments (213 topical, 7 editorial, 0 hidden)

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

There are other ways to do it, and there are conditions under which that assumption can be relaxed.

So what's the most appropriate method?

by vladimir on Mon Mar 16th, 2009 at 09:38:39 AM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

I would use weighted averages, as I said above. You can play with them in different ways to get different kinds of information, but as long as we don't have any really good ways to estimate uncertainties, there is no way you'll ever get a "significance test" in the ordinary sense of the term.

I have to run now, but if you'd like, I can play around with a couple of different measures when I get home, to see what comes out.

- Jake

Friends come and go. Enemies accumulate.

by JakeS (JangoSierra 'at' gmail 'dot' com) on Mon Mar 16th, 2009 at 09:43:06 AM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

What exactly is your null hypothesis?

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

by Carrie (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 09:44:41 AM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 Carrie (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 09:59:35 AM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 Carrie (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 12:00:58 PM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 Carrie (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 12:07:43 PM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 Carrie (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 11:58:49 AM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 Carrie (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 12:08:23 PM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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 Carrie (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 12:16:15 PM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

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

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

By which I mean, in an unbiased court, what would you expect the number of indictments to be proportional to? We have had a large number of incompatible measures thrown about for days.

You'd probably end up with a test for the parameter of a Poisson distribution or something, not a mean and standard deviation of a Gaussian.

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

by Carrie (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 09:58:56 AM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

So it's Poisson we should be using.

by vladimir on Mon Mar 16th, 2009 at 10:06:30 AM EST
[ Parent ]

Re: A Statistical Analysis of the ICTY's bias. (none / 0)

Yes, but you need a sensible null hypothesis for the behaviour of an unbiased court.

And then you can do a test for the rate of conviction which is a Bernouilli test.

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

by Carrie (migeru at eurotrib dot com) on Mon Mar 16th, 2009 at 10:07:50 AM EST
[ Parent ]

A Statistical Analysis of the ICTY's bias. | 220 comments (213 topical, 7 editorial, 0 hidden)

Top Diaries

Ireland 2023 Rugby World Cup Squad selected

Integrating Ukraine Into NATO Family

Leinster's demise and Munster's hope

Southern Irish disinterest in Northern Ireland affairs

The end is Nigh?

Joe Biden. America's Interventionist Hero

The law of conservation of transness

Recent Diaries

Bi-Partisan Effort to Undermine Democracy

June 2023

Ireland 2023 Rugby World Cup Squad selected

Integrating Ukraine Into NATO Family

Southern Irish disinterest in Northern Ireland affairs

Incident Ukrainian War Display Gets Int'l Attention

German Climate Activists Group Outlawed

Leinster's demise and Munster's hope

Joe Biden. America's Interventionist Hero

Targeted Assassinations: a Bankrupt Strategy

The end is Nigh?

Hijacking Peace by Zelensky for War Escalation

UA Drone Attack On Moscow

May 2023

The law of conservation of transness

US Provoked Conflict In Europe

U.S. Will Be Ousted From Middle-East

Settler Extremism Blessed by Jerusalem Leaders

Occasional Series