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by Kati
22 Feb 2004 20:20
Forum: Nuclear Issues Archive
Topic: Pakistan Nuclear Proliferation - 20 Feb 2004
Replies: 334
Views: 70676

Re: Pakistan Nuclear Proliferation - 20 Feb 2004

To Sridhar and others: Parvaiz Hoodboy (or Hoodbhoy) is a qualified researcher, and above all he is on uncle's payroll. Recruiting top scientists (by uncle) in developing countries (at advanced research centers) is a result of cold war, and started in sixties. Several bharatiya deshi vignyanis are o...
by Kati
20 Feb 2004 22:00
Forum: Nuclear Issues Archive
Topic: Pakistan Nuclear Proliferation - 20 Feb 2004
Replies: 334
Views: 70676

Re: Pakistan Nuclear Proliferation - 20 Feb 2004

British Financial Times (http://www.ft.com) has been slicing and dicing pakistan in last few issues doggedly (unlike the US media). here is an assortment of articles: 1. Pakistan's Khan sold nuclear parts to Iran and Libya (feb 20, 2004) http://search.ft.com/search/article.html?id=040220000464&q...
by Kati
19 Sep 2003 17:25
Forum: Nuclear Issues Archive
Topic: Saudi Arabia's nuclear ambitions
Replies: 48
Views: 17840

Re: Saudi Arabia's nuclear ambitions

I think this is a psy-op by KSA. By leaking this report, and then denying it officially, they are trying to protest to the US. Sort of - "If you push us too hard, then we'll go the other extreme". And there'll be some countries, groups who are willing to swall the billions of $$s of KSA bait - under...
by Kati
03 Jul 2002 02:44
Forum: Nuclear Issues Archive
Topic: Seismology for Dummies: Guesstimating nuke test yields
Replies: 150
Views: 33026

Re: Seismology for Dummies: Guesstimating nuke test yields

Not totally.
Every time we have a data set, we need to play with it. Some times, the conventional methods work, sometimes not. if not then go thru careful transformations of data (popular one is- `Box-Cox
transformation') to see what makes the model assumptions valid.
by Kati
03 Jul 2002 02:01
Forum: Nuclear Issues Archive
Topic: Seismology for Dummies: Guesstimating nuke test yields
Replies: 150
Views: 33026

Re: Seismology for Dummies: Guesstimating nuke test yields

Sunil: It is not a simple question of difference of errors. It was like approximating an apple by an orange. The standard regression models assume equality of error variances (Called `homoscadasticity) and independence of individual errors. But when model was fitted and residual analysis was done (t...
by Kati
03 Jul 2002 00:43
Forum: Nuclear Issues Archive
Topic: Seismology for Dummies: Guesstimating nuke test yields
Replies: 150
Views: 33026

Re: Seismology for Dummies: Guesstimating nuke test yields

http://www.ctbtcommission.org/blancpaper.htm Check the second diagram (three scatter plots-red, blue and green). How well can we fit the scatter plots is the moot point. This is basically called `Regression'. A small change in curve fitting can lead to great deal of differences in final `inference'.
by Kati
03 Jul 2002 00:29
Forum: Nuclear Issues Archive
Topic: Seismology for Dummies: Guesstimating nuke test yields
Replies: 150
Views: 33026

Re: Seismology for Dummies: Guesstimating nuke test yields

Yes, we looked into a few data-sets (not related to the Indian tests) where things could have been done in a better way. I can give you specific references in mid August after I'm back from vacation.

In the meantime take a look at this article:
http://www.llnl.gov/str/Walter.html
by Kati
02 Jul 2002 23:33
Forum: Nuclear Issues Archive
Topic: Seismology for Dummies: Guesstimating nuke test yields
Replies: 150
Views: 33026

Re: Seismology for Dummies: Guesstimating nuke test yields

Two things: 1. The challanger case: estimating the stress that a particular metal (or material) can withstand is an old statistical problem. In general, the life time of a material is modelled by various probability models, like exponential model, gamma model, Weibull model etc. Inappropriate modell...
by Kati
02 Jul 2002 22:00
Forum: Nuclear Issues Archive
Topic: Seismology for Dummies: Guesstimating nuke test yields
Replies: 150
Views: 33026

Re: Seismology for Dummies: Guesstimating nuke test yields

For Shiv and others: Estimation of Nuke test yields is based on, what is known as Inverse regression in Mathematical Statistics (or sometimes known as `Calibration Problem'), several model assumptions. Yes, the value of `a' (4.04 or 1.1) can greatly affect the estimation procedure, and it depends on...

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