From: lambert@spectrum.cs.unsw.oz.au (Tim Lambert)
Subject: Re: Gun control (was Re: democratic platform)
Organization: none
	<1992Aug26.223723.10095@ms.uky.edu>
Date: 1 Sep 92 18:15:00

>>>>> On Wed, 26 Aug 1992 22:37:23 GMT, uk09365@nx05.mik.uky.edu (robert i kesten) said:

> In article <LAMBERT.92Aug27012957@henna.spectrum.cs.unsw.oz.au>  
> lambert@spectrum.cs.unsw.oz.au (Tim Lambert) writes:
>> concerned with investigating and refuting claims such as "one
>> million crimes are stopped each year with guns",

> 	You claimed that this number had to include criminals
> 	defending against other criminals while ignoring the
> 	fact that the main underlying research (the Hart poll)
> 	was of registered voters (not likely to include felons
> 	or other criminals.)

If you want to find out how often people stop crimes with guns there
are two obvious ways to find out.

1. You can ask people if they were victimized by a crime or an
attempted crime, and whether they stopped that crime with a gun.  This
what the NCS does, and gives rise to a an estimate of about 65,000
crimes stopped each year with guns.

2. You can ask criminals how often they were thwarted by armed
victims.  This is what Wright & Rossi did.  34% of the criminals that
they surveyed admitted this.  These criminals had an average of 10
prior arrests, so if the 34% who had been thwarted had an average of
two thwartings each, it would appear that being arrested is 15 times
as likely for these criminals as being stopped by an armed victim.
Combine this with about 988,000 arrests per year (this number from
Kleck's "Crime Control" paper) and we get a (very rough) estimate of
70,000 crimes stopped each year with guns.

The Hart poll asked whether a handgun had been used for
self-protection, which will include most with-gun assaults.  If you
want to use this number for "crimes stopped", you need to provide some
evidence that registered voters never commit gun crimes.  I note
that in the US, 50% of homicides are committed by people with no prior
convictions, and thus could be registered voters.

>> "gun training caused
>> rapes to plummet in Orlando",

> 	If I remember correctly you said this was not true
> 	because the rate had dropped 100% (to 0) in a previous
> 	year.  You neglected that the previous drop was from
> 	something like 14 to 0 and the one after the gun training
> 	program was from ~34 to 4.

Yes, if it can drop all the way to zero without gun training, how can
you say that the gun training caused a drop to a slightly higher
level?  In short, the decrease was not statistically significant.

>> "Kennesaw burglaries fell dramatically
>> after gun ownership was made compulsory",

> 	80% drop, what (briefly) was your refutation of this.
> 	Sorry that I missed / forgot it.

An 80% drop according to Kennesaw's mayor, a strong advocate of
Kennesaw's ordinance.  If instead you look at UCR statistics, you will
discover that there was no decrease at all.  See Criminology 29:4
p541-559 (1991).  This article uses interrupted time series analysis
to examine rapes in Orlando, burglaries in Kennesaw, robberies in KC,
and burglaries in Morton Grove and Evanston (the last two to see if
the handgun bans encouraged burglaries).  The only statistically
significant effect was in Morton Grove, where there was a significant
DECREASE in burglaries following the handgun ban.

>> "medical data shows that a
>> gun is no more deadly than a knife", etc etc.

> 	There is medical data which shows that some knife wounds
> 	(from large knives and icepicks) are just slightly less
> 	deadly than the average single handgun wound.

I believe that the medical data you refer to is in Annal of Surgery
153:5 p639-649 (1961), and it shows no such thing.  It is true that
the mortality rate for pistol wounds was 16.8%, for ice pick wounds
was 14.3% and for "butcher knife" wounds was 13.3%.  However, someone
who presents the data this way is either totally ignorant of
statistics or being deliberately misleading.  The same data shows that
the mortality rate for rifle wounds is 7.7%, which seems rather
unlikely.  The problem is that these rates are based on far too little
data to be meaningful.  There were only two deaths in the sample from
"butcher knives", meaning that a 95% confidence interval for mortality
rate from butcher knives is between 4 and 38%, which isn't very
useful.  Furthermore, the data only includes people who survived long
enough to make it to hospital, and is for the 1950's (treatment may
have improved since then).

Newsgroups: talk.politics.guns