Friday, 26 April 2013

Errors in the book (including interesting Binomial distribution error)

Eagle-eyed readers continue to point out errors in the book and we regularly update the Errata page here with the changes:

An especially interesting error (with a fair few ramifications) has been discovered in Example 5.6 on pages 122-23.  The error was triggered in our calculation of the 99th percentile of the particular Binomial distribution there. Basically we wanted to know the following:
what is the number k for which the probability of tossing at least k heads in 100 tosses is 0.01?
Now, because the Binomial is a discrete distribution there is no reason why there should be an integer k for which the probability of tossing at least k heads in 100 tosses is exactly 0.01. In fact it turns out that:
  • for k=61 the probability is 0.017
  • for k=62 the probability is 0.0105
  • for k=63 the probability is 0.006
So, in the original manuscript we just used k=62 because that was easily the closest to 0.01.

However, to make the point in the example to work it was important that the probability was LESS than 0.01. So, whereas the example used k=62, what we strictly needed was k=63. This meant all the subsequent calculations were wrong.
There were also some other errors in the example including a couple that had been introduced by the publishers as they were correct in our final manuscript.

Thursday, 11 April 2013

Bayesian networks plagiarism

If, as they say, imitation is the sincerest form of flattery then we are privileged to have discovered (thanks to a tip off by Philip Leicester) that our work on Bayesian network idioms - first published in Neil M, Fenton NE, Nielsen L, ''Building large-scale Bayesian Networks'', The Knowledge Engineering Review, 15(3), 257-284, 2000 (and covered extensively in Chapter 7 of our book) has been re-published - almost verbatim -  in the following publication:
Milan Tuba and Dusan Bulatovic, "Design of an Intruder Detection System Based on Bayesian Networks", WSEAS Transactions on Computers, 5(9), pp 799-809, May 2009. ISSN: 1109-2750

The whole of Section 3 ("Some design aspects of large Bayesian networks") - which constitutes 6 out of the 10 pages - is lifted from our 2000 paper.  Our work was partly inspired by the work of Laskey and Mahoney. The authors reference that work but, of course, not ours, hence confirming the very deliberate plagiarism.

Milan Tuba and Dusan Bulatovic are at the Megatrend University of Belgrade (which we understand is a small private University) and we had not come across them before now. The journal WSEAS Transactions on Computers seems to be an example of one of the dubious journals exposed in this week's New York Times article. Curiously enough, after a colleague distributed that article yesterday I was going to write back to him saying that I disagreed with the rather elitist tone of the article, which suggests that the peer review process of the 'reputable scientific journals' was somehow unimpeachable - in reality there is no consensus on what journals are 'reputable' and even the refereeing of those widely considered to be the best is increasingly erratic and at times bordering on corrupt (which is inevitable when it relies exclusively on volunteer academics).  But at least I would hope that any 'reputable' journal would still be alert to the kind of plagiarism we now see here.

This is not the first time our work has been very blatantly plagiarised. Interestingly, on a previous occasion it was in a book that was published by Wiley Finance (who I am sure are widely considered one of the most reputable publishers). The book was 'written' by a guy who had been our PhD student for a short time at City University before he vanished without notice or explanation. The book contained large chunks of our work (none of which the 'author' had contributed to, as it predated his time as a PhD student with us) without any attribution. Despite informing Wiley of this, and proving to them that a) the author's qualifications as stated in the book were bogus; and b) the endorsements on the back cover were fraudulent, they did nothing about it.