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Let Our Research TakeThe Work Out Of Yours.If data analysis is your problem HP hasdeveloped the statistical tools you need forspeeding research and cutting costs. These fastacculrate conmputation systems can handle any taskfrom routine data reduction and examination allthe way up to advanced statistical andmathematical analysis.Are you doing applied research? Basic stat

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1850), noting that the atomic weightsof various elements were almost exactlyinteger multiples of the atomic weightof hydrogen, inferred that atoms ofvarious elements consisted of commonconstituents. He correctly recognizedthat the relationship, although notexactly true, pointed toward a basicscientific law. At the other extreme, allfour presidents of the United Stateswho have been assassinated in officehave been elected in years ending inzero. In spite of the low a priori prob-ability of this occurring, no one wouldseriously suLggest that this points to aphysical or sociological law.

Since 1971, two more World Serieshave lasted seven games. The proba-bility of a single series of evenlvmatched teamns lasting seven games is

1=(2 =6

where C is the binomial coefficient.The probability of two successive

series lasting seven games is therefore25/256, or approximately 0.1. Whilenot quite as improbable as the reputedloss of two vital magnetic tapes, this isnevertheless somewhat surprising.Now that 17 of the 29 World Series

played since the end of World War IIhave lasted seven games, one finds thatthe probability of this occurring as arandom event (between evenly matchedteams) wotuld be

29

E Cn p- (1 - P)9 = 0.0021it = 17

And, of the 21 World Series that havegone to the sixth game since the endof World War II, the team that wasahead, going into the sixth game, hasstill won only four times. If the teamsare evenly matched, the probability ofwinning less than five times is now

C (2)Iin 0.0036

This "back-to-the-wall" effect, whichtends to favor the trailing team in thesixth game, has occurred only sincethe end of World War II. Once again,one is forced to ask whether this un-usual occurrence of seven-game WorldScries is aI statistical freak or whether.like Prout's hypothesis, it suggests theexistence of some hitherto undetectedpheniomeiion.

WILLIAM SIMONSchool of AMedicine and Dentis try,Unhiersity of Rochlester,Rochester. Neew York 14642

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Most ofyour Blo Med problemscan be solved by an unknown.

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