Statistics Hacks
by Bruce Frey

This errata page lists errors outstanding in the most recent printing.

If you have technical questions or error reports, you can send them to
booktech@oreilly.com.  Please specify the printing date of your copy.

This page was updated June 25, 2008.

Here's a key to the markup:
	[page-number]: serious technical mistake
	{page-number}: minor technical mistake
	<page-number>: important language/formatting problem
	(page-number): language change or minor formatting problem
	?page-number?: reader question or request for clarification



Confirmed errors:

[5]  middle paragraph;
From the author: Statements defining the mean as "as close as possible to other scores" are incorrect. The mean actually minimizes the squared distances, not the distances.

Thanks to S. Davies in an Amazon.com review for pointing this out.


{10}  middle of the page;
The description of the additive rule as applying to any one of a group of
"independent" events is confusing at best and wrong at worst. The probability of any
one of several "mutually exclusive" events occurring IS the sum of the individual
event's probabilities. The author uses the word "independent" to mean that events
cannot co-occur, and, therefore, are mutually exclusive. As S. Davies in an
Amazon.com review pounts out, however, the word "independent" is more likely (and
more commonly) interpreted as meaning that whether an event occurs or not is
unrelated to whether any other events occur, which has an opposite meaning from
"mutually exclusive". Thanks to S. Davies for pointing this out.


(39) Table 1-10 Effect size standards;
Caption should read "Effect size", not "Effect sze".


(56) 1st paragraph;
The 2nd sentence should read "...to estimate future college success", not "future college admission".


(160) 4th paragraph;
The example of a simple imaginary game where you would win money over the long haul is not explained well, because of an editing error. Replace the third sentence with "The other half of the time you would lose one dollar."


(182)  Last paragraph;
Most whole numbers in the text have commas in them, for example 4,968,601. However,
in the fraction on the last line of the page only the numerator has commas in it,
which is a bit confusing.
You might change
/6497400
to
/6,497,400


{196} middle of page, Probability of all 6 attempts failing
.8086 = .278
should be:
.8086^6 = .278


{197}  second line;
The equation says "90^10 = .349", but it should read ".90^10 = .349".