ML20074A740

Affidavit of I Levi Clarifying 830211 Testimony Re Suggested Method of Making Sensible Probability Judgments Described in Section 5

ML20074A740
Person / Time
Site:	Indian Point
Issue date:	05/10/1983
From:	Levi I AUDUBON SOCIETY, FRIENDS OF THE EARTH
To:
Shared Package
ML20074A737	List: ML20074A736 ML20074A740
References
ISSUANCES-SP, NUDOCS 8305160028
Download: ML20074A740 (2)

Text

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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION ATOMIC SAFETY AND LICENSING BOAR F Before Administrative Judges:

Jamesi.'*G1eason, Chairman P

Dr. Oscar H. Paris Frederick J. Shon In the Matter of x

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x Docket Nos.

CONSOLIDATED EDISON COMPANY OF x

NEW YORK (Indian Point Unit 2')

x 50-247-SP x

50-286-SP

~ POWER AUTHORITY OF THE STATE OF x

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' Tdy T ~1983

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NEW YORK (IMid Point Unit 3) x x

x AFFIDAVIT OF ISAAC LEVI I,

Isaac Levi, being duly sworn, state as follows:

1.

In my testimony in this proceeding on February 11, 1983 (Tr. 7823-7828), in answer to questions by Judge Frederick J. Shon, I explained the suggested method of making sensible probability judgements described in Section Five cf my written testimony, and indicated the significance of my illustrative examples.

Upon review of my answer, I believe that it should be clarified.

2.

The method of determining worst permissible priors employed in my testimony was based on a simplifying assumption stated on page 37 of my written testimony.

This simplifying assumption--that the event, all of whose points are assigned

~densityg, ~shoti1d imve total probability.5 - implies th'at

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p x = o((1-x) =

.5.

By removing this simplifying assumption so that /x could be greater than

.5, one may obtain mean values-for worst permissible priors indefinitely close to the upper end of the assessed range of values of A.

w 8305160028 830510 PDR ADOCK 05000247 0

PDR 9

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3.

Thus, the small variation in mean values of X d

in my examples, which were pointed out by Judge Shon, depen /s._

on a simplifying assumption which is heavily biassed in favor of IPPSS.

The decision as to what value to assign tojG x 4.

is, like the value of k, a reflection of the caution of the investigator, that is, how much indeterminacy he seeks to put in his prior judgement.

As stated in my testimony, when-ever there is a dispute-on this point, one should be more rather than less cautious.

It should be noted that the assessed range used in 5.

the example I took from the Reactor Safety Study as reported in IPPSS is only one order of magnitude.

Hence, it is to be expected that the difference in both mean and median estimates will be less than an order of magnitude when relying on these assessed intervals.

Other examples could turn out quite We can only find out by doing the calculations different.

in IPPSS along the lines I have suggested.

Finally, on line 24 of page 7826 of the transcript, 6.

" medians" should read 'Ineans,"and vice versa at the end of the sentence.

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Isaac Levi Subscribed and sworn to before me

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this /d th day of May, 1983 NOTARY PUBLIC P; chi..'C M. HARTZMAN h0TARY e4,041". 3TME OF NEW YORK Nc.

1-4.Th39 Commisvan Empirt. Manh 30.g1 8' Qualified in tv<w ' fork Cou a

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