--- In FairfieldLife@yahoogroups.com, new.morning <[EMAIL PROTECTED]> wrote: > > --- In FairfieldLife@yahoogroups.com, "authfriend" <jstein@> wrote: > > > > --- In FairfieldLife@yahoogroups.com, TurquoiseB <no_reply@> wrote: > > > > > > --- In FairfieldLife@yahoogroups.com, "sparaig" <sparaig@> wrote: > > > > > > > > --- In FairfieldLife@yahoogroups.com, new.morning <no_reply@> > > wrote: > > > > > > > > > > http://istpp.org/crime_prevention/voodoo_rebuttal.html#note1 > > <snip> > > > > > And later, he dismisses a doubling of the murder rate during the > > > > > course from 10/mo to 20/, as an "outlier". Thats convenient. > > > > Actually that would be 10 and 20 per week, not per > > month. > > > > > > It was an outlier within the course itself. It was a one-week > > > > aberration due to a gang fight that saw 10 deaths in one > > > > incident, IIRC. > > > > > > Yeah, new...it's perfectly legitimate to "not count" an > > > anomalous event like *that*! What are you *thinking*? > > > If you bitch about something as miniscule as disregarding > > > data because it doesn't fit the all-important expectations, > > > why you could set a precedent. > > > > Actually, statistically speaking, anomalous events > > are just that, anomalous, and may *not* be relevant > > when one is considering longer-term trends. > > > > This is from the article new morning cites: > > > > Park asserts that levels of violence actually increased to record > > levels. He confuses homicides which accounted for only 3% of > > violent crime in Washington during 1993 with violent crimes in > > general. Park asserts that the murder rate soared during the > > experiment, and claims that "participants in the project seemed > > serenely unaware of the mounting carnage around them." > > > > It is true the murder rate did not drop during the course as we > > acknowledged in the initial research report and in the published > > study but the facts were very different. For six weeks ending the > > month before the experiment, from mid-March through April, homicides > > in Washington averaged ten per week. Beginning one week after the > > course and for twelve weeks thereafter, homicides also averaged ten > > per week. During the eight weeks of the experiment, in June and July, > > the average was again ten per week except for one horrific 36- hour > > period in which ten people died. Apart from this brief episode, which > > was a statistical outlier, the level of homicides during June and > > July of 1993 was not significantly higher than the remainder of the > > year. > > > > According to his article, Park apparently took his lead on the murder > > issue from a Washington Post reporter who had been impressed that the > > one 36-hour period had led to a sudden doubling of the murder rate > > that week. The reporter, and Park, did not notice that the very next > > week the murder rate dropped from its common rate of ten by more than > > twice that is, the totals went up to 20 one week and down to 4 the > > next. This is precisely the type of sporadic fluctuation one must > > account for when total numbers are small. The average incidence of > > murder in Washington was little more than one per day, and with > > numbers as low as this, as Park and all scientists know, random > > fluctuations can appear extremely high when listed as percentages. > > > > As I said in an earlier post, I'd sure like > > new morning to elucidate what he thinks is > > wrong with this explanation of why the fact > > that the murder rate jumped during one 36- > > hour period should not be considered significant > > with regard to the overall study results. > > I DO think the gang shooting should be considered significant. That > was my point.
Yes, I believe I said I'd like you to say what you thought was wrong with the explanation as to why it should not be considered significant. <snip> > In re-reading the paragraphs, its ambiguous as to whether > the outlier was actually excluded from the analysis. Yeah, I don't think it was excluded. > If it was excluded, (which > was my take upon writing the original post, I do not feel that there > was sufficient explanation as to why the gang-shooting was so > extraoridnary out of the ordinary that it should not be included. Remember, what the guy is defending against is the accusation by the critic that the 36-hour spike in the murder rate meant the whole study was a complete failure. What he's doing is explaining why it didn't mean that at all. On the other hand, the numbers involved wouldn't be enough to significantly affect the results even if the murder spike *had* been included. > Second, a key premise of the rebuttal was that temperature "nailed" > variations in crime. It was said to be a very tight fit to the sesonal > crime data. This is key in distinguishing ME from some other factors > in crime reduction. Yet, with a deeper look, there is still huge > variations in crime, even after crime has been controlled by > temperature (and other factors). But not as "huge" as the drop in the rate during the course, right? Thus, it points towards other > possible major factors which have not been controlled for in the core > crime model (without ME). This raises serious questions to whether it > was ME or other uncontrolled for factors that were driving the > changes. And/or there simply is a lot of "static", unexplained or > random variations in the crime rate. In either case, its a difficult > "base case" from which to clearly isolate an ME during the period of > its intervention. What about the fact that there is normally such a small number of murders (only 3 percent of violent crime in 1993 as a whole)? Is it not the case that, as he says, "with numbers as low as this...random fluctuations can appear extremely high when listed as percentages"? In any case, I'm not sure in what way your second objection relates to the point he was trying to make, i.e., that the spike doesn't affect the study's conclusions. > Third, the rebuttal reinforces the fact that murder, rape and > assualts, were summed. These are qualitatively different acts. At a > minimum, separate analysis of each type of crime should have been > analyzed. If only one or two types of violent crime went dowm and the > other(s), did not, it raises quesions as to why, and IMO, would place > doubt on ME. By averaging, with assaults being by far the highest > category, the study becomes essentially a study on assaults. Effects > on murders and to a lesser degree, rapes, are submerged. This makes sense to me as a criticism of the study design. Why they chose to lump all violent crime together isn't entirely clear, but I can't imagine they did this because they *expected* the murder rate to spike and *wanted* to submerge it. I suspect they did it because it wouldn't sound as impressive, PR-wise, to claim a decline merely in assaults, as opposed to a decline in all violent crime; and to do studies on all three types of violent crime separately would just have been too complicated. My guess is they figured the number of rapes and murders would be small enough that they wouldn't significantly affect the results either way in any case, so they might as well include them. Anyway, I'm *still* not clear why you think his explanation for why the spike didn't invalidate the study, as the critic claimed, lessens his credibility, whether the additional murders were included in the totals or not. (BTW, thanks for keeping your response simple and relatively jargon-free!)
