Kates Cuts

[jerryd]

Jeff,

The City Police had a suspect in mind by late September, 1888 and staked him out the night Eddowes was murdered. Whomever he was, the stakeout was in the area of your Zone 1. (Possibly Zone 3. I can't tell from your map exactly.)

[JeffHamm]

A few thousand, in fact; Dorset Street alone had close to 800 residents at any one time.

Yes, exactly, this analysis doesn't identify individual people, it suggests areas to search as they have a higher probability of producing leads. Simply searching all of Whitechappel at random is going to be far more time consuming, and inefficient, then searching based upon a prioritized search strategy - provided that strategy is actually better than chance!

One can also use these to prioritize who in a list to investigate first. I don't mean a list of people for which there are actual investigative leads per se, but rather, when you have a list of people, say "let's get the names of all the butchers", then you might order that list based upon those who live in high probability zones, and work your way down. Again, real investigative leads trump any probability based strategy. If the police had information that suggested Joe Bloggs, who lives in a low probability zone, was connected to the offenses, you ignore the zone and follow the real evidence. But sometimes people are dismissed from investigations prematurely, and there have been cases where noting that someone "no longer being looked at" turns out to be in a high probability zone and gets another look, and as a result turns out the case gets solved (something like this happened with Comeaux, who was police officer and the Layfaette Southside Rapist as his residence at the time of rapes was in the highest probability zone produced by Rigel, although he had moved since that time so wasn't living there anymore, when his name came up the investigating officer checked the files and found where he used to live corresponded to the profile - his DNA was later matched to the crimes). It was the real evidence that solved the case, it was the profile that helped prioritize following that particular lead earlier rather than later.

- Jeff

[JeffHamm]

Im confused about the Geographic Profile. Doesnt the algorithm assume JTR chose the murder locations?

To a certain extent, yes, but not to the level of specificity that it matters so much if, as appears likely in this case, the victims chose the specific location. JtR still had to be in the area after all, so in that sense he chose the area. He had to find a suitable victim, which could occur anywhere in the areas he goes and he's still willing to commit an offense. The probability of finding a victim will be related to a number of things, such as concentration of potential victims, but also where the offender spends more time. Offenders will tend to spend more time within a certain distance of what are referred to as "anchor points", which are things like residence, work, and so forth - places we spend large amounts of out time in our every day life. For some offenders, of course, an anchor point might be capturing an area they spend a lot of time in only during "hunting", for example, but that is part of their every day life. It's just an activity most people do not do. But, with regards to an investigation, even if that is the case, it means there is a greater probability of finding information about who the offender is in that area. While the output is, of course, dependent upon the specific inputted locations in the specific details, the overall general pattern is fairly robust against minor changes, like moving the various crime locations a bit in random directions, we would still end up with a similar looking result in the global sense. Remember, the idea is not to end up with a specific address (though of course, that would be wonderful if it were possible), but rather to suggest general areas where actual investigation might have a better chance of producing leads.

Basically, had JtR found different victims, in different locations, the pattern of those hypothetical offenses would be expected to produce an output that also reflects a similar area. And indeed, if we include, for example, Tabram (as some people argue she may have been a victim of JtR as well), things don't change all that much. If we remove Stride, as her inclusion is highly debated, things shift somewhat, but we still end up with a high probability zone in roughly the same area.

David Berkowitz (Son of Sam), lived quite far from where he committed his crimes. However, at the time he committed his first offense, he lived pretty close to it and moved away after that. He also worked at the JFK Airport for some period of time, and that location from his first address travels right through the bulk of his offenses. He was returning to an area he was very familiar with. The analysis locates his former residence in zone 13 (upper Yellow square), and the airport is around zone 19-21 (these are just crudely placed markers for illustration, and it's not a great map to begin with). He also worked in the Bronx as a postal worker, but I don't know where that was. I suspect, though, there is something in the primary zone in Queens that he was associated with, and that he could be found there quite frequently. He was eventually identified because his car got a parking ticket, and it was near the Brooklyn offense. Turns out, he used his own car during all of them, and I would suspect his car would be noted in that area as well. I don't know enough about his life to know for sure if he did have some sort of regular activity in Queens, but I would be a bit surprised if there's not something there that he was associated with. And therefore, that means, that is an area where he could potentially have come to police attention. I've not looked much into this case, and would want a far better map to work with, mostly because his residence in Yonkers makes him a commuter in that sense. However, his former residence, and his airport workplace, and other such anchor points, means he's not associated with the region of the crimes, so he's a marauder in that sense. (The marauder/commuter distinction is very blurry when one tries to define it - but for testing purposes of routines like this being able to locate residences is a way to keep the conditions all the same).



Anyway, you can think of geographical profiling as a sort of low-spatial frequency filter, the specific details of the exact locations are "blurred", and the underlying global pattern is what is being emphasized and extracted.

And finally, one must never forget, there are offenders who do not correspond to the general pattern. They are less common (which is why there is a general pattern in the first place), but uncommon situations do occur. These are not "evidence", they are, however, not random either and because investigations get solved by finding leads, what these do is prioritize an order of where to search for leads. For example, whether JtR lived in the highlighted area, or whether he only was there when "hunting", is immaterial. Police patrolling that area could be told to take note of all males walking around at night, identify them if that is within the law, and find out who is seen there regularly. Many will have valid and innocent reasons, but the offender's name may come up on that list, and that's one more chance of linking them to something else. For example, if Joe Bloggs shows up as being known to be in the area very often at night, and he turns out to be a butcher, fitting the witness descriptions, and so forth, then he would be someone worth investigating further. Further investigation might exclude him, or it might not.

I've included Berkowitz here to illustrate that. He didn't live in the area (after he moved), his former address and one of his workplaces are in the area, though neither is in the highest priority zones (13 is a bit mid-way, still way better than chance, but it would take awhile to get there from an investigative point of view). I've not come across any references to him having an association with Queens, but I've not looked that hard as he's a "on the shelf" series in my research as he's a "residence commuter", making him less useful to me for testing the routines. I'm digressing now, but just wanting to point out that while these are often pretty good, they still must not be treated as "absolutely the truth".

- Jeff

[Observer]

I meant that it was academic purely in terms of the geographical profile, which is what was under discussion. If the women were died near where they lived (which they all did), and if the killer lived in the same area (which he probably did), then the geo-profle is going to look pretty much identical whether the women chose the locations or not.

Right, I see what you mean.

[Sam Flynn]

Not quite academic to those who believe that Stride, Eddowes, and Kelly were not soliciting prior to their deaths.

I meant that it was academic purely in terms of the geographical profile, which is what was under discussion. If the women were died near where they lived (which they all did), and if the killer lived in the same area (which he probably did), then the geo-profle is going to look pretty much identical whether the women chose the locations or not.

[Fisherman]

The reasons are bleeding obvious why he almost certainly lived in that area Fisherman. Though Im guessing by your responses your fav Suspect for every unsolved murder occurring in the East End in the 1880's didn't.

Letīs set you straight directly here:

What is "bleeding obvious" to some people is less so to others - that is the nature of things. Besides, many serial killers have not lived where they perpetrated their crimes, so there is nothing bleeeding obvious to see here.

My favourite suspect is not a suspect for every unsolved murder in the East End of the 1880:s, Iīm afraid. He is a suspect for every unsolved murder involving mutilations and eviscerations (and that takes us back into the 1870:s too, mind you), and that is because mutilators and eviscerators are rarer than a useful comment from you these days. I have him down for a round dozen murders, just about, give or take a few. That would not even put him in the top 100 when it comes to number of victims, so hinting at it being very strange if he killed numerous victims is simply wrong. Killing a dozen victims, probably prostitutes most or all of them, is middle of the road, sadly.

And of course, he lived directly adjacent to what is described as the murder area out here, and passed through that area on a daily basis. He has more proven opportunity and is a better geographical fit than any other suspect suggested, so whaddayouknow - you got that wrong too.

The four Stooges you have down for the canonical five murders would be a much, much rarer thing than a common evisceration killer. Then again, you donīt care much about the realities of these things, do you? Itīs all about nose cutting mafias, deluded sheep butchers and personal deeds for you, is it not? Of course, it may be that I am wrong about that - itīs just that it seems so bleeding obvious...

Goodnight, Michael.

[Michael W Richards]

Not quite academic to those who believe that Stride, Eddowes, and Kelly were not soliciting prior to their deaths.

Surely if the three ladies in question, plus Nichols and Chapman, were soliciting when they met JTR then in my opinion it's highly likely they chose the location where they were to meet their deaths.

There is no evidence to suggest that those three were indeed soliciting at the time Observer, so I hear that. But as for Kelly, by being in her own room and in her underwear she really didn't choose anyplace in particular. She was at home. Pretty much every woman in the East End or London for that matter who was at home at the time was safe too.

[Michael W Richards]

Any ten year old messenger boy would be extremely well aquainted with the streets he worked. Anybody who had stayed in the area for many years and then moved away would have the same insights. Hansom cab drivers, carmen (!), prostitutes etc, would have it too. The idea that the killer must have resided in the very area where he killed is not true - at all.
And that is the "spin" I am putting on it.

The reasons are bleeding obvious why he almost certainly lived in that area Fisherman. Though Im guessing by your responses your fav Suspect for every unsolved murder occurring in the East End in the 1880's didn't.

[Observer]

Of course, if the killer and his victims were based in the same small area, then whoever chose the locations becomes somewhat academic. Unless he had private transport, the murders were always likely to happen within easy walking distance of where both killer and victim lived.

Not quite academic to those who believe that Stride, Eddowes, and Kelly were not soliciting prior to their deaths.

Surely if the three ladies in question, plus Nichols and Chapman, were soliciting when they met JTR then in my opinion it's highly likely they chose the location where they were to meet their deaths.

[Fisherman]

Considering that Nichols was murdered in Bucks Row Fisherman, I don't see why that area can't extend to Doveton Street

True enough, of course. I guess what I am saying is that placing our bets only on residence sites would be foolhardy. Many other parameters must be weighed in.

[Fisherman]

I know how youd like to spin this bit of debate,

You DO? And here I was, trying to obscure it!! I should have known that you would see right through me.

... but it seems clear to most ...

No no no - donīt think that you can voice what "the most" would beleive, Michael. Stick with your own convictions, and donīt try to push them down peoples throats.

that to know the area intimately enough to travel avenues/alleys, streets that allowed him to remain unseen leaving any alleged Ripper murder scene, he had to be travelling on foot.

Of course not. You can get an extremely intimate and precise view of a street net by way of travelling it by car(t).

He picked up Polly and Annie while on foot and left the same way, someone killed Liz and left on foot, Its hard to imagine someone not being on foot from Mitre Square, and someone using a small courtyard with only one way out means they had to leave on foot there.

If you think that I am saying that the killer employed a cart on his murderous outings, you are wrong. I am saying that somebody can get a good enough overview of the street layout by means of using a car(t) to enable him/her to keep track of escape routes, etcetera. And therefore, we should not predispose that the killer must have lived in the area to be killing there; he could be well enough aquainted with the streets for a large variety of reasons anyway. THAT is what I am saying.

If someone had to have egress from all the sites on foot, it stands to reason he would know where to walk, where to turn, what alleys turn into other streets, where cover is...etc. That's walking knowledge of the area. Someone who would walk from the train station to a local job, someone who would take a hansom into the area for work, they would not be exposed to the entire realm that these killings took place within.

Any ten year old messenger boy would be extremely well aquainted with the streets he worked. Anybody who had stayed in the area for many years and then moved away would have the same insights. Hansom cab drivers, carmen (!), prostitutes etc, would have it too. The idea that the killer must have resided in the very area where he killed is not true - at all.
And that is the "spin" I am putting on it.

[Michael W Richards]

Not agreed - being on foot in many ways limits your possibilities of taking in an area compared to driving around in it. The latter allows for a much more extensive covering of ground. Imagine that you want to quickly find out the layout of the streets in an area. Which will serve you better and quicker - doing it on foot or by car(t)?

Being on foot admittedly allows for learning about doorways and cramped alleyways, but who says the Ripper used any such knowledge? A cab driver would be excellently suited to learn and understand the streets and passageways in an area.

There is of course also the possibility that the killer had extensive former experience of the area but had moved slightly away to, say, the northeast. Why, he could even be using the exact same streets in his occupation - on foot!

Who knows? (Hint: somebody you are debating with, perhaps?)

I know how youd like to spin this bit of debate, but it seems clear to most that to know the area intimately enough to travel avenues/alleys, streets that allowed him to remain unseen leaving any alleged Ripper murder scene, he had to be travelling on foot. He picked up Polly and Annie while on foot and left the same way, someone killed Liz and left on foot, Its hard to imagine someone not being on foot from Mitre Square, and someone using a small courtyard with only one way out means they had to leave on foot there. If someone had to have egress from all the sites on foot, it stands to reason he would know where to walk, where to turn, what alleys turn into other streets, where cover is...etc. That's walking knowledge of the area. Someone who would walk from the train station to a local job, someone who would take a hansom into the area for work, they would not be exposed to the entire realm that these killings took place within.

[Observer]

It is actually not a fact that he DID live in the area, Observer.

Considering that Nichols was murdered in Bucks Row Fisherman, I don't see why that area can't extend to Doveton Street

[Michael W Richards]

If he wanted to make it look like a Ripper murder, he could just have "ripped" her belly open ā la Polly Nichols. Instead, he excised a uterus, a section of colon and a kidney - in near darkness!!! - thereby exceeding anything the Ripper had done up to that point. This was Jack the Ripper, alright, make no mistake.

You may well be right, Im not as convinced as you though.

[Fisherman]

Jack the Ripper was almost certainly always on foot, which requires a lot more intimate knowledge of an area than driving around it does. In my own life I know several walking paths that shorten the distance between 2 points rather than using streets or roads, and they are also less visible as a result.

Not agreed - being on foot in many ways limits your possibilities of taking in an area compared to driving around in it. The latter allows for a much more extensive covering of ground. Imagine that you want to quickly find out the layout of the streets in an area. Which will serve you better and quicker - doing it on foot or by car(t)?

Being on foot admittedly allows for learning about doorways and cramped alleyways, but who says the Ripper used any such knowledge? A cab driver would be excellently suited to learn and understand the streets and passageways in an area.

There is of course also the possibility that the killer had extensive former experience of the area but had moved slightly away to, say, the northeast. Why, he could even be using the exact same streets in his occupation - on foot!

Who knows? (Hint: somebody you are debating with, perhaps?)