Location of Annie Millwood's attack

[JeffHamm]

Hi all,
Have made a couple of improvements in the profiling routines, just some slight modifications that have improved the performance a bit. I thought I would have a look at how the various choices that have been suggested at one time or another influence the resulting profiles. So I started with the C5, then added Tabram, then Millwood, then McKenzie (the inclusion of Millwood is speculation that if Jack is responsible for Tabram then Millwood looks like an early failed attempt. One of the contemporary views was that Tabram was definitely part of the same series, while McNaughten, for one excluded her. I can't recall who at the moment, but one of the Doctors (Phillips maybe?) didn't think Eddowes was by the same person. Today, of course, there is debate around Stride. And as then, some now include McKenzie as well. So, I thought I would try some of those combinations.

I've listed the output for the suspects in the order they ranked as per the C5 plot (which shows their location by the box next to their ranking number - not sure how visible they are here though). Note, Chapman, at number 13, was not actually living at this address at the time of the C5, but was to the south east on Cable street. That's off the map. I've left him on it just so people can know where he eventually was. I believe there is some question around Tumblety as well. And Druit is only speculated to have access to the location indicated.

Anyway, I've also made a couple modifications to the visualization. Zone 1 is now yellow, but the magenta/pink bit in the centre of it represents the highest 1% (each zone is 5%). Zones 2-4 are in the orange areas, and this helps highlight some of the secondary peaks of interest. Zones 5-8 are a lighter shade of red, again, to aid in detecting where lower peaks may be occurring (and, when the contours are drawn in, that helps to quickly work out what zone you're looking at; I left the contours off as shrinking the images to post them here degrades the image and the contours look awful.

Anyway, here are the zone scores for the various outputs, which are shown below. Note, Sagar's suspect falls in the top 1% priority zone for the C5, which is what the asterisk is indicating.

In short, while things shift around, as one would expect, the overall pattern is pretty stable in that it remains in the Western area. The biggest shift is when Stride is removed, and personally that, and the secondary peak over by Nichols, have always interested me as good places to look. Curiously, none of the suspects have the decency to locate themselves there.

Oh well. Enjoy.

- Jeff

C5 +Tabram +Millwood C5+TMMc C5-Stride C5-Edd
Sagar’s Suspect (*1) ( 4) ( 5) ( 4) (13) (48)
Levy .................( 2) ( 3) ( 4) ( 2) (13) (36)
Barnett .............( 2) ( 1) ( 3) ( 3) ( 2) (13)

Druitt ...............( 8) (20) (14) (14) (19) (81)
Hospital ............( 9) (13) (18) (17) (17) ( 9)
Bachart ............(13) (12) (16) (12) (38) (56)

Hutchinson .......(11) ( 2) ( 2) ( 2) ( 8) ( 1)
Tumblety ..........(14) ( 8) (25) ( 22) (60) ( 6)
Peabody House .(16) (15) ( 7) ( 8) ( 7) (25)

Cohen .............(19) (12) (18) (21) (46) (33)
Pizer ...............(25) (21) (25) (26) (70) (19)
Kosminski ........(28) (27) (32) (31) (65) (35)

Chapman .........(30) (12) (11) ( 9) (41) (23)
Kaminsky .........(34) (35) (36) (35) (45) (55)

[Ginger]

Hello Ginger

The location of the apron is, I'd have thought, as relevant from a geographical profiling perspective as its owner's dead body in Mitre Square. The apron's being dropped in the doorway, in itself a conscious act, says "Jack was 'ere" even more than the graffito does, because we don't know that the latter was written by the killer. For that reason, certain loopy theories aside, the presence of the apron in Goulston Street is a sure marker of where Jack was at some point after Eddowes' murder.

Hi Sam

I'll certainly stipulate that the apron fragment marks a place where the Ripper passed, and that he was almost certainly on his way home, or to a place of refuge, after having murdered Eddowes. There is, of course, a non-zero chance that it was carried by a dog or some other agency to its final location, but I think the odds of that are so low that it can be safely lumped in with the loopy theories. Beyond a reasonable doubt, then, the Ripper left it at or within a few feet of the place where it was found.

The evidence that this forms a meaningful act on Jack's part is rather less compelling, I believe, and all the moreso when we exclude the graffito from consideration. Were it left by the message to show its provenance or just to draw attention, that's obviously a meaningful act. If he had simply finished using it and tossed it without really thinking (as I believe), or even dropped it without realizing that he had done so, then it carries no message from the killer - it simply documents his presence, like an animal leaving tracks. If that's the case, then it doesn't form a valid data point for Jeff's mapping algorithm, since its location tells us nothing about the killer's perceptions of where it would be safe to leave evidence.

Now, the thing is, IF the Ripper wrote the message, then the message is the true data point for the limited purpose of determining the Ripper's 'safe zone'. Writing a message definitely shows intent. It shows a place, just like the murder locations, where he was familiar enough with the area that he felt at home there, and safe leaving evidence, but not so close to his actual dwelling as to invite undue scrutiny.

That's why I formulated my question to be about the message rather than about the apron. That's what I had on my mind at that point. My initial belief was that the graffito wasn't written by the Ripper, and if including it in the data set radically distorted the results, I was going to take that as pretty good evidence that the graffito (a deliberate act) wasn't the Ripper's, AND that the apron piece had been thoughtlessly discarded or accidentally dropped (as opposed to deliberately placed) as Jack was leaving his killing zone. We got the opposite result, of course.

On balance, I still believe that the graffito wasn't Jack's, and that the apron placement really shows nothing more than a place that he passed. It happens to be deeply enough inside his killing zone that it doesn't distort the pattern, but I think that's still weak evidence for deliberate placement. Jack liked to shock people, and I think that had he intended a message, it would have been rather more dramatic. That's perhaps prejudiced thinking on my part, but I think on balance of evidence that it's likely to be correct.

[Sam Flynn]

Hello Ginger

The location of the apron is, I'd have thought, as relevant from a geographical profiling perspective as its owner's dead body in Mitre Square. The apron's being dropped in the doorway, in itself a conscious act, says "Jack was 'ere" even more than the graffito does, because we don't know that the latter was written by the killer. For that reason, certain loopy theories aside, the presence of the apron in Goulston Street is a sure marker of where Jack was at some point after Eddowes' murder.

[Ginger]

Thanks for taking the time to do that. I appreciate it. I hadn't considered the issue of weighting the results by including multiple related events.

The reason I'd consider the graffito to be of greater significance than the apron fragment, at least for this purpose, is that the graffito was definitely the result of a conscious decision-making process, and would have taken IMHO at least a minute to have written. If the writer was in fact the murderer, then for the time it took to write that, he stood exposed on a public street engaged in an incriminating activity. Whether or not he ever consciously considered the matter of why the location felt safe or attractive to him, I have to think that his criteria for choosing the general area for the deed would have been the same ones he used for choosing murder locations. I say 'general area', because in the matter of the graffito, a victim didn't need to be present, which was a factor operating in the choice of exact murder locations that wasn't present here. Nonetheless, I think the general areas for murders and graffito would have been chosen similarly.

It's in this matter of risk-taking and deliberate intent that I think the graffito excels the apron fragment as evidence of where the Ripper (if indeed it was he who wrote it) felt safe. The apron fragment could have been casually or surreptitiously tossed aside where it was found. It's the act of a second, and discarding it in that fashion is arguably less risky to the killer than retaining it hidden upon his person. The location where it was jettisoned, by itself, therefore says little about Jack's sense of the place as safe. If he wrote the message, however, then he did so either while in possession of that fragment of apron, or having just thrown it to the ground nearby. That's definitely a risky behaviour, and where he would do that says something about his perceived areas of safety, just as where he committed murders does.

Edit: I was actually wondering if the location of the graffito, considered as a crime scene, would radically distort the results. It doesn't seem to. I certainly accept that the Ripper passed by this way, as shown by the presence of the apron fragment. For the reasons outlined above (and the fact that it could have been dropped accidentally), that doesn't really speak to whether Goulston Street was a 'safe' place to him in the way that the graffito (if his work) does.

[JeffHamm]

Personally, I think he jettisoned it en route from Mitre Square to the safety of his "home". Either way, it's probable that Goulston Street was handily placed for him.

I tend to lean towards that as well. It does appear to be taken to wipe his hands and knife, etc, and I think he just tossed it when done. I'm not convinced he stopped to write on walls.

- Jeff

[Sam Flynn]

Yes, the question is, when did the apron get there? Did JtR drop it as he fled, and it was just not spotted for an hour or so, or did he bolt home, and then drop it there later, after having made it home and was now out on the streets again?

Personally, I think he jettisoned it en route from Mitre Square to the safety of his "home". Either way, it's probable that Goulston Street was handily placed for him.

[JeffHamm]

Happily, we can ignore the controversial graffito in this context, I think, because the apron piece alone indicates that the killer was there at some point.

Yes, the question is, when did the apron get there? Did JtR drop it as he fled, and it was just not spotted for an hour or so, or did he bolt home, and then drop it there later, after having made it home and was now out on the streets again?

- Jeff

[Sam Flynn]

what happens if the Goulston Street Graffito is treated as a crime scene? ... If it's his work, then I'd have to think that the same factors that operated in his choice of murder scenes would have operated in his choice of a place to write his message.

Happily, we can ignore the controversial graffito in this context, I think, because the apron piece alone indicates that the killer was there at some point.

[JeffHamm]

My apologies if this has been dealt with already, and I've overlooked it, but I'm curious - what happens if the Goulston Street Graffito is treated as a crime scene? Obviously it wasn't a murder, yet if Jack wrote it, he was standing out on a public street doing something that could easily have put his neck in a noose (as he tended to do). If it's his work, then I'd have to think that the same factors that operated in his choice of murder scenes would have operated in his choice of a place to write his message.

I've not done that in any of these, so you've not overlooked it. There are things to consider when entering secondary locations of interest, such as, once we enter the Graffito location, we know it's tied to the Eddowes case, so we're in a way weighting that case more than the others. But, if we include Stride, we also know those two events are tied together (meaning, if we include Stride in the series, then the fact that JtR then heads west to end up at Eddowes' location is a decision that is in part based on being in Stride's location to start with. In some ways, that could complicate the inclusion of Eddowes as that location could be less representative of the offender's anchor point (meaning, his home usually). If we include the Graffito, we are sort of doing the same again, but potentially distorting things more because Eddowes' location is already a bit contaminated. That being said, I don't think the distortions are really all that large in a practical sense most of the times. I think there is potentially a lot of information from direction of travel (Stride - > Eddowes -> Ghoulston street, shows parts of the path the offender chose to travel, combining that knowledge with the profile map is part of interpreting the maps.) Anyway, I've done the C5 analysis with the Graffito included, which you can compare with the previous C5 map (not the Rossmo versions). I've listed the suspects below, the old C5 zones first, and the new ones 2nd. I've reordered the list to correspond to this map (so the suspects are listed in order of priority as per the map below:



Geographical profile outputs:
Suspect …………Zone (C5 / C5 + Graffiti)

Gouston Str. Graffiti ( 3 / 2*) – this isn’t a suspect, but we know JtR was here at some point – was he near home? – in the 2^nd analysis this is entered as a geographical data point

Levy ........................ ( 2 / 2) - I know nothing of this suspect other than I spotted a post on them
Barnet .................... ( 3 / 2)
PC Sagar’s Suspect ..( 1 / 3) - And the police were actually watching someone here!
Hutchinson ............. ( 13 / 6)
Peabody House ……. ( 17 / 9) (there’s no suspect here; I mislocated Hutchinson here before)

Bachert .................. ( 12 / 12) – Another suspect I know nothing about, other than he was on the
vigilant committees and was a bit of a nuisance to the police at the
time.
Druitt / Ludwig ....... ( 9 / 13) Druitt is suggested to have had access to Dr. Thyne's surgery, and
given his cricket schedule, seems almost ruled out; Ludwig
was ruled out as he was in custody on the double event
Donston/Hospital ... ( 7/ 17) – This also fits the “mad doctor/medical student” ideas
David Cohen .......... ( 19 / 18)
Klowoski ................. (26 / 18) – Chapman, but he was on Cabel Street, moved here after JtR series

Tumblety ................ (16 / 30) There is some question as to whether he was here in 1888 or not
Pizer ....................... (27 / 32) - Pizer was cleared (although officially identified as Leather Apron)
Kosminski ............... (30 / 35)
Kaminsky ................ (32 / 36)


- Jeff

[Ginger]

My apologies if this has been dealt with already, and I've overlooked it, but I'm curious - what happens if the Goulston Street Graffito is treated as a crime scene? Obviously it wasn't a murder, yet if Jack wrote it, he was standing out on a public street doing something that could easily have put his neck in a noose (as he tended to do). If it's his work, then I'd have to think that the same factors that operated in his choice of murder scenes would have operated in his choice of a place to write his message.

[JeffHamm]

Hi again,

I've programmed up routines to do geographical profiling based upon Rossmo's routines, which is used in actual police investigations and has contributed useful information to a number of cases, although at times, like any model of complex behaviour, doesn't get it right every time (while that would be nice, human's are a bit more complicated than that). Rossmo's approach, and he was the first to really bring the idea of using offense locations to locate offender's "anchor point" into a usable format, can be thought of as making predictions about the minimum distance an offender has traveled to commit an offense. He also uses "Manhattan Distances" (which is based upon a square rather than a circle, like Euclidean distances), which is why you can see square hotspots around some of the offenses. I don't have time to summarize the suspects just now, but will try and do that later. When I compared my routines with Rossmo's on the cases above and a couple others that I have (another zone 1, and a zone 22 case, for both approaches), there wasn't a dramatic difference in the solutions for most cases (Rossmo had "better zones" for 3, there was no difference in zones for 2, and I had better zones for 5, but in terms of absolute percentage of area searched, it was pretty much an even split as Rossmo's approach had the two tied zones slightly higher in the zone). Rossmo's approach was better with DeSalvo (Boston Strangler) but missed quite badly with the Phoenix Case, and that's a case where the offender's minimum distance is much larger than in the other cases. What I'm trying to do is base the predictions on more predictors, and not just rely on the accuracy of the minimum distance estimation. So, I'm actually pretty pleased with how this project is coming along as my limited performance tests are showing that these routines are at least as good as what's used, and at the moment, shows a marked improvement with some of the cases where current routines will miss things.

Anyway, below are the results for the C5+2 (Millwood and Tabram), C5, and the C5 without Stride. The only comment I'll make is that Sagar's suspect and Hutchinson both look to be in high priority zones; meaning, they tend to fall close to the estimated minimum Manhattan distance from an offense (or a local cluster of offenses).

- Jeff

[JeffHamm]

Hi,

Ok, I've been working on some new ideas with the geographical profiling routines that I'm developing. What I do is analyse a bunch of cases I have, which are about 30 or so cases of serial arson in New Zealand. To be honest, serial arson is a pretty hard type of crime to geographically profile because a big part of the spatial decision making is not up to the offender (vacant lots, abandoned buildings, schools, etc, are limited in choice from which to choose). Also, I never expected the equations that I've been developing based upon arson to translate to other types of serial offending (serial rape and/or serial murder). However, as maps of those crimes were relatively easy to find on the net, I've had a go at checking out one or two, expecting it to show that "crime specific values" are required (so while the approach might work for serial rape and/or serial murder, the specific equations would be slightly different, and one would need a set of those types of crimes from which to obtain the values; another reason I started building up a collection of them). Surprisingly, though, the same routines that I've been using the arson cases to develop the routines seem to work quite well. I've been able to obtain the information I need from 8 cases of serial rape and/or murder. These are not used to set the parameters, but to test the values I obtain from the arson cases (otherwise, it's not really a test of generalization). And, yes, if you're wondering if that's perhaps a bit small for a proper test sample size, you are absolutely correct. But, for now, it's what I've got. Eventually I hope to continue to add more cases to this, which will give a better idea of how well it's doing.

Anyway, now that I've programmed in the new bits, there were a number of options to explore in terms of which model produced the most reliable set of results, and I've finished that with my 8 test cases (the one listed as "Canter & Larken, 1993) is from a paper on spatial crime scene analysis, and is a pattern of offenses during a serial rape case in the US, but I know nothing more about it. The good news is that the additions have improved the results, with 2 cases not changing zones (both were in zone 1 before, and still are), 5 cases improving between 1 and 6 zones (average 3), and only one case dropping a zone (DeAngelo went from zone 2 down to zone 3). Here's the table of results, the %Searched is basically just how much of the "chance search space" would you have to search if you simply followed the geographical output exactly. The 50% and 75% are just indicating the point where 1/2 and 3/4 of my test cases fall (so, 3/4 of the test cases fall in or below zone 7). All of them were located better than a random search, so that was encouraging (and the Phoenix case I had the map for since 2016 or so, but they've only recently made an arrest and I found the address in the court documents online. It was good to see he falls in the red zone as this was a new addition to the test cases (he also has an unusual pattern, so I'm not actually disappointed that he's in a fairly high zone - it's still better than chance, and he is unusual. Also, DeSalvo has tended to be elusive to the routines up until now, generally falling in zone 20 in my previous best models (Lonnie Franklin, the Grim Sleeper, also tended to be lowish, at zone 12 in the previous models).

So, here's the performance of the current best model I've got on solved cases, all far more recent than the JtR series. After that, I'll put this new model's profile maps for the C5+2, and the C5, and the C5 - Stride. I'll list the POIs from above, and their zone numbers, in that order. I'm going to re-arrange them based upon their C5 zone rankings if things change, so they might be in a different order from before. I'm writing this as I'm doing these analyses for the first time with the improved models, so it may be that they look pretty much as before (in fact, I'm not expecting any dramatic changes, but there could be some shifting about):

			Zone	% Searched
Dennis Rader (BTK)			1	3.01
Ted Bundy (offenses )			1	4.21
Canter & Larkin, 1993 figure			1	4.5
Joseph James DeAngelo			3	13.92	50%
Bruce McArthur (Toronto)			6	27.73
Lonnie Franklin (Grim Sleeper)			7	33.93	75%
Albert Desalvo (Bos. Strangler)			14	69.22
Phoenix Serial Shooter			15	73.7
------------------------------------------------------------------------------
	mean		6	28.78
	sd		5.73	28.68
	Median		4.5	20.83
	worse than chance		0

New Geographical profile outputs:

Suspect ………..….Zone (C5+2 / C5 / C5-Stride)
Sagar’s Suspect …………( 4 / 1 / 14) - And the police were actually watching someone here!
Levy ........................ ( 2 / 2 / 14 ) - I know nothing of this suspect other than I spotted a post on them
Gouston Str. Graffiti …. ( 1 / 3 / 5 ) - this isn’t a suspect, but we know JtR was here at some point after Eddowes - was he near home?
Barnet ...................... ( 3 / 3 / 2 ) – Using Kelly’s location

{ This is the end of the 50% cut off POIs --------------------------------- }
Donston/Hospital ………. ( 18 / 7 / 19 ) - This also fits the “mad doctor/medical student” ideas

{ This is the end of the 75% cut off POIs --------------------------------- }
Druitt / Ludwig ........... ( 16 / 9 / 22) Druitt is suggested to have had access to Dr. Thyne's surgery, and given his cricket schedule, seems almost ruled out; Ludwig was ruled out as he was in custody on the double event
Bachert ..................... ( 12 / 9 / 50) - Another suspect I know nothing about, other than he was on the vigilant committees and was a bit of a nuisance to the police at the time.
Hutchinson ................ ( 3 / 13 / 10 )
Tumblety ................... ( 30 / 16 / 54) There is some question as to whether he was here in 1888 or not
Peabody House ……………( 9 / 17 / 8) (there’s no suspect here; I mislocated Hutchinson here before so I leave it in)
David Cohen .............. ( 18 / 19 / 50)
{ ----------------------------------------------------------------------
These POIs fall in zones that get considered pretty much “excluded” except *:
------------------------------------------------------------------------ }
Klowoski .................... ( 13* / 26 / 49) - Chapman, however apparently this wasn’t his address in the Autumn of 1888 and he was on Cable Street, just south of the map (guessing in a 40+ zone)
Pizer ......................... ( 29 / 27 / 70) - Pizer was cleared (although officially identified as Leather Apron)
Kosminski .................. ( 35 / 30 / 68 )
Kaminsky ................... ( 40 / 32 / 51)

And the maps (interesting, the C5 map still has an easterly zone, but it's now the one up closer to Nichols, not the southern one. I tended to think the one that now remains made more sense in some ways (close to first in the series, and so forth), so I'm a bit chuffed to see it's now back:



- Jeff

P.S. No doubt, things will change again at some point.

[JeffHamm]

Rader used a motorised vehicle, though I note that you said in your previous post that ~20% of killers are commuters, but I wonder whether that would apply to the 19th century, when access to private transport was significantly less common than it became in the latter half of the 20th? It would be fascinating to know how the "catchment areas" of Victorian killers compared to those of their more mobile successors.

Yes, Rader had access to a car, but that just means the scale changes, he travels in kilometers (or miles, since he's in the US) and JtR works in meters/yards. The routines I've been working on use the crime pattern itself to deal with patterns invariant of the scale of physical measurement, so it recognizes a pattern whether the offender is travelling by foot, bike, or car, etc. Of course, I'm working with modern crimes, so most have access to vehicles, so your concern is not without merit and is something I eventually want to ensure is a safe assumption to make.

And remember, commuters are just offenders who reside outside the crime zone, which is defined as the smallest circle that encloses all the crimes (although this is often then expanded by increasing the radius of that circle by 10-25% on the assumption that the estimated crime zone is a bit smaller than it really is). A quick and dirty, but quite accurate, way of estimating this is to just take the two offense locations that are most distant from each other, and use them to define a circle (which one could expand 10-25%). Basically, an offender that lives outside the circle is a commuter and those who live inside are called "marauders" - the majority of offenders are marauders. Again, if you're travelling by foot, the crime zone will be smaller, so commuters will be closer. I tend to expand by 25% because "near commuters", those juts outside the crime zone, show similar patterns to definite marauders. Things start to break down after that, at least with the data set I have to work with.

That said, there could very well be differences in the percentage of commuters / marauders between now and Victorian times. If I were to guess, I would think commuters are more common now, not because they have cars etc (that just let's them expand the scale of their crime zones) but because crime detection is no longer a new thing, and commuting is an attempt to hinder investigation.

- Jeff

[Sam Flynn]

...split the area of high interest between close to the bulk of the crimes, but there is another pattern slightly less common, which is for the offender to be closer to the less dense end of the crime zone (Dennis Rader, for example; the bulk of his crimes were quite far south, with two in Park City, where he lived.)

Rader used a motorised vehicle, though I note that you said in your previous post that ~20% of killers are commuters, but I wonder whether that would apply to the 19th century, when access to private transport was significantly less common than it became in the latter half of the 20th? It would be fascinating to know how the "catchment areas" of Victorian killers compared to those of their more mobile successors.

[JeffHamm]

So much for finally. I've toned back some of the weights in the more complicated routines and have redone the C5. This is looking closer to what I sort of expected it to do, which is, start to split the area of high interest between close to the bulk of the crimes, but there is another pattern slightly less common, which is for the offender to be closer to the less dense end of the crime zone (Dennis Rader, for example; the bulk of his crimes were quite far south, with two in Park City, where he lived.) The JtR pattern is a bit similar in some aspects to how Rader's crimes were distributed, just more east-west rather than north south. So, seeing a zone to the east start to pop up makes sense as the analysis should draw attention to both possible patterns. Previously, it was zooming in on that area at the expense of the more common "dense end" zone. I was thinking it would be the one to the north, closer to Nichols, but that's dropped down to a zone 3 peak.

It's late here now, so I won't detail the suspects in the format above, and just list them here: Sagar's suspect and Levy are in Zone 1, the Grafitti is in zone 2, the Hospital tucks into zone 4, Barnett is in zone 5, Bachert zone 9, Hutchinson and Tumblety zone 11, Druitt zone 14, David Cohen zone 17, the Peabody house zone 20, Pizer 22, Klowoski 23, Kosminski 25, and Kaminsky 28.



- Jeff