4-Aug-86 22:18:09-PDT,8265;000000000000 Mail-From: NEUMANN created at 4-Aug-86 22:16:05 Date: Mon 4 Aug 86 22:16:05-PDT From: RISKS FORUM (Peter G. Neumann -- Coordinator) Subject: RISKS-3.30 Sender: NEUMANN@CSL.SRI.COM To: RISKS-LIST@CSL.SRI.COM RISKS-LIST: RISKS-FORUM Digest, Monday, 4 August 1986 Volume 3 : Issue 30 FORUM ON RISKS TO THE PUBLIC IN COMPUTER SYSTEMS ACM Committee on Computers and Public Policy, Peter G. Neumann, moderator Contents: Ozone hole undetected (Jeffrey Mogul) Re: Risks of CAD (Henry Spencer) Comment on Hartford Civic Roof Design (Richard S D'Ippolito) Expert system to catch spies (Larry Van Sickle) The RISKS Forum is moderated. Contributions should be relevant, sound, in good taste, objective, coherent, concise, nonrepetitious. Diversity is welcome. (Contributions to RISKS@CSL.SRI.COM, Requests to RISKS-Request@CSL.SRI.COM) (Back issues Vol i Issue j available in CSL.SRI.COM:RISKS-i.j. Summary Contents in MAXj for each i; Vol 1: RISKS-1.46; Vol 2: RISKS-2.57.) ---------------------------------------------------------------------- From: mogul@decwrl.DEC.COM (Jeffrey Mogul) Date: 4 Aug 1986 1058-PDT (Monday) To: Risks@csl.sri.com Subject: Ozone hole undetected Although I, too, am relying on memory, I'm pretty sure that the article Bill McGarry mentioned was published in The New Yorker sometime during the past two or three months. [Also something in Science a few issues ago on the phenonenon itself... PGN] My understanding is that it was not so much a case of the researchers believing the satellite instead of other evidence, but rather that the researchers who ran the satellite must not have been too terribly interested in what was going on over the poles. After all, if they were interested, I would think they might have been bothered by large empty spots in their data. As to Bill's being disturbed that "the satellite would observe this huge drop in the ozone level year after year and just throw the results away", I think this imputes a certain level of intelligence to the computer system that probably isn't there. I'd bet that their computer spits out maps of the ozone layer, but probably doesn't have any facility to spot trends. Still, it's obvious that a little more care in the decision to discard anomalous data would have gone a long way. When humans through away anomalous results, at least they realize that they are doing so [although not always consciously; see Stephen Jay Gould's "The Mismeasure of Man".] When a computer throws away anomalous data, the user might not be aware that anything unusual is going on. A good program would at least remark that it has thrown away some fraction of the input data, to alert the user that something might be amiss. ------------------------------ From: decwrl!decvax!utzoo!henry@ucbvax.Berkeley.EDU Date: Sun, 3 Aug 86 03:17:32 edt To: decvax!CSL.SRI.COM!RISKS Subject: Re: Risks of CAD Alan Wexelblat comments: > Petroski also fears that inadequate computer simulation is replacing crucial > real testing... One can see examples of the sort of engineering this produces in many pieces of high-tech US military equipment. In the recent times, the criteria used to evaluate a new military system have increasingly drifted away from straight field-test results and toward complex and arbitrary scoring schemes only vaguely related to real use. Consider how many official reports on the Sergeant York air-defence gun concluded, essentially, "no serious problems", when people participating in actual trials clearly knew better. Some of this was probably deliberate obfuscation -- juggling the scoring scheme to make the results look good -- but this was possible only because the evaluation process was well divorced from the field trials. Another infamous example is the study a decade or so ago which seriously contended that the F-15 would have a kill ratio of several hundred to one against typical opposition. These are conspicuous cases because the evaluation results are so grossly unrealistic, but a lot of this goes on, and the result is unreliable equipment with poor performance. It should be noted, however, that there is "real testing" and real testing. Even the most realistic testing is usually no better than a fair facsimile of worst-case real conditions. The shuttle boosters superficially looked all right because conditions had never been bad enough to produce major failure. The Copperhead laser-guided antitank shell looks good until you note that most testing has been in places like Arizona, not in the cloud and drizzle more typical of a land war in Europe. Trustworthy test results come from real efforts to produce realistic conditions and vary them as much as possible; witness the lengthy and elaborate tests a new aircraft gets. Even if the results of CAD do get real-world testing, one has to wonder whether those tests will be scattered data points to "validate" the output of simulations, as opposed to thorough efforts to uncover subtle flaws that may be hiding between the data points. Henry Spencer @ U of Toronto Zoology {allegra,ihnp4,decvax,pyramid}!utzoo!henry ------------------------------ Date: 4 Aug 1986 00:33:41-EDT From: Richard.S.D'Ippolito@sei.cmu.edu Subject: Comment on Hartford Civic Roof Design Apparently-To: Risks@SRI-CSL.ARPA I would like to point out that Alan Wexelblat's comment on inadequate use of computers for CAD might be somewhat misleading regarding the roof modelling for the Hartford Civic Center. The problem was that the program user selected the wrong model for the beam connection to be used. When the program was re-run with the correct model, it predicted the collapse in precisely the mode that it happened. I'm not sure that that was clear from the wording in Mr. Wexelblat's comment, i.e., that the modelling was improperly done by the operator (GIGO again!). Richard D'Ippolito, P.E. Carnegie-Mellon University Software Engineering Institute (412)268-6752 rsd@SEI.CMU.EDU ------------------------------ Date: Wednesday, 23 July 1986 22:39-EDT From: CS.VANSICKLE at R20.UTEXAS.EDU To: AIList [REMAILED TO RISKS BY HERB LIN] Re: Expert system to catch spies Today's (July 23, 1986) Wall Street Journal contains an editorial by Paul M. Rosa urging the use of expert systems to identify potential spies (acutally traitors). Mr. Rosa is a lawyer and a former intelligence analyst. Since virtually all American traitors sell out for money, an expert system embodying the expertise of trained investigators could examine credit histories, court files, registers of titled assets such as real estate and vehicles, airline reservations, telephone records, income tax returns, bank transactions, use of passports, and issuance of visas. The system would look for suspicious patterns and alert counter-intelligence officials for further investigation. There are some obvious considerations of privacy and legality, but that is probably best discussed on another bulletin board. Mr. Rosa says the system would be used only on the 4.3 million people who hold security clearances, who have consented to government scrutiny. According to Mr. Rosa, "the obstacles to implementation are not technological," and "the system could be implemented quickly and cheaply." He predicts that the Soviets, working through their extensive international banking network, will use the same techniques to identify potential recruits. He also says that the FBI has three expert systems for monitoring labor rackets, narcotics shipments, and terrorist activities. Any reactions? Is this doable? It strikes me as more of a data collection problem than an expert system problem. Is there anyone who knows more about the FBI expert systems and can talk about it? Larry Van Sickle cs.vansickle@r20.utexas.edu Computer Sciences Dept. U of Texas at Austin Austin, TX 78712 ------------------------------ End of RISKS-FORUM Digest ************************ -------