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  • #16
    Originally posted by Darryl Kenyon View Post
    Hi Jeff
    Would it be possible to do a map with the C5 plus Martha but minus Kate out of said C5 ? The reason being I am one of those that believe the killer had a second bolt hole near Mitre Sq which he used on that one particular murder. Hence the apron not being discovered in Goulston street until the later time.

    Regards Darryl
    Hi Darryl,

    Sure. That would look like this:

    Click image for larger version

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    The Rigel routines include a "buffer-zone" in the calculations, meaning the offender is thought to be "close" to offense locations but not "too close". It also bases distances on "Manhattan distances", so you total the horizontal and vertical distances between two points (as the cab drives) rather than the "Euclidian distance", which is the distance in a straight line (as the crow flies). This is why the Rigel outputs tend to have sharp corners and such, as the underlying geometry is based upon "squares" rather than "circles".

    Other routines, like those in "Dragnet" (by Canter), do not include a buffer zone (hence the highlighted areas right around offenses; this doesn't always happen, but does sometimes, as in this example), and tend to be based upon Euclidian distances. For example, if I do the above using Dragnet routines, we would get this, which produces a more rounded looking output due to the underlying geometry is based upon circles:

    Click image for larger version

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    And my own routines ("Dr. Watson"), also employ Euclidian distances, but the analysis is based upon a number of different underlying patterns, which then get combined. One pattern is a general "distance decay from the offenses", but uses a different calculation from Dragnet, and because it involves other spatial aspects, it doesn't tend to produce "spikes" at individual crime locations .

    Click image for larger version

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    All three sets of routines work equally well, meaning if I give them all a bunch of different cases, on the whole they produce similar results over the entire set. Obviously, for any individual case, one routine may work better than another, but that is neither here nor there when evaluating the generality of the routines.

    And while at first glance the areas look different, in the end, they are all highlighting very similar regions really. At some point I want to try and take all three routines and combine their output to see if that in anyway improves performance. It's like getting three opinions, and looking for where those opinions agree. Whether or not that improves things is an empirical question though, and at the moment I've not started on that.

    - Jeff





    Comment


    • #17
      Oh, and I should say about the above routines, both work far better than random chance as well. Performance declines as the number of offenses declines, in the sense that as the number of offenses decreases the estimated "territory size" gets bigger. Generally, the crime zone area is calculated as the area of the smallest circle that encloses all of the offense locations - then the territory size is estimated by inflating this based upon the number of offenses, with fewer offenses resulting in a greater inflation factor. Then, the spatial routines produce a jeopardy map by calculating a priority value at each pixel of the inputted map. These are then arranged from highest to lowest, and grouped into "zones", with each zone comprising 2.5% of the estimated territory size. And you map out the zones, in this case stopping when you reach the number of zones required to reach the 75% probability criterion.

      Although the above would indicate that Dr. Watson requires fewer zones, Dragnet the next, and Rigel the most, I'm not convinced those values are stable. I've got some analyses I have to do when I get an appropriate amount of time to devote to this, and my suspicions are that in the end the cut off zones will end up being the same for all three routines. While it would be nice for my ego if my routines out performed the others, I suspect they will end up being similar to the others. One of the major difficulties, actually, is getting a sufficient number of reliable maps to work with that don't come from a biased selection set. Maps included in the literature tend to be "exemplars", meaning, a map that work really really well for a given routine, so when one includes those in a test set, you bias the test set towards the routine that the article favors. (Note, this isn't deceptive on the articles part, as the demonstration is presented as just that, an exemplar of how well the routines can work; but it is an issue I have when trying to test the efficacy of the routines as I want the good, the bad, and the ugly!).

      - Jeff

      Comment


      • #18
        Originally posted by JeffHamm View Post

        That's the Rigel output (developed by Kim Rossmo). The output shows the highest "peaks". However, while well above chance in terms of locating an offender's anchor point (and yes, their residence is usually one anchor point, but others might be place of work, or as you suggest, a pub they frequent). The "zones" expand outwards, and in some work that I've done examining how well various routines do locate an offender's residence (not just any anchor point), in order to have a 75% probability of locating the residence inside the suggested search area, it has to expand out to something like this:

        Click image for larger version Name:	JackMap_Rigel.jpg Views:	0 Size:	156.6 KB ID:	825831

        If I include Martha Tabram to the C5, we get this:

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        If instead I include Alice McKenzie to the C5 we get:

        Click image for larger version Name:	JackMap_Rigel_AM_SOL.jpg Views:	0 Size:	154.2 KB ID:	825833

        and if I add both, we get:

        Click image for larger version Name:	JackMap_Rigel_MT_AM_SOL.jpg Views:	0 Size:	151.1 KB ID:	825834

        So your instincts are correct, there isn't much of a change as a result of adding either or both to the pattern produced by the C5.

        One thing, however, is that these kinds of spatial analyses are thought to reflect underlying decisions being made by the offender. However, that need not be the case here. In the JtR series, we do have to keep in mind that the victims behaviour and choice of locations are not as independent as those of a serial killer who picks people at random throughout a city. In this case, many of the victims will be frequenting pubs, as you mentioned, or if soliciting, then probably going to similar areas. As a result, the spatial analysis could very well be picking up common spatial patterns of the victims, rather than something about JtR per se.

        Moreover, there are other routines (equations), that are at least as successful as Rigel in narrowing down and prioritizing the search area. For the C5, they tend to also produce a peak area in a similar vicinity as the Rigel one, but shifted N slightly (running between Miller's Court and 29 Hanbury Street).

        Anyway, that being said, having looked at these a few times, if the spatial analysis is picking up on JtR's choices as well, I also think the pubs up in that general area would be a good place to start looking.

        - Jeff
        Forgive me if I'm mistaking the reading of the images but would The Queen's Head pub be the one to focus on in terms of the killer potentially meeting/getting familiar with the victims or would-be victims?

        Comment


        • #19
          Originally posted by Curious Cat View Post

          Forgive me if I'm mistaking the reading of the images but would The Queen's Head pub be the one to focus on in terms of the killer potentially meeting/getting familiar with the victims or would-be victims?
          The Queen's Head would be one to focus on, but not the only one. The Britania Pub (East end of Dorset Street) and The Ten Bells are also in the area of interest, and I wouldn't overlook The Horn of Plenty (west end of Dorset Street) or the Golden Heart Pub (corner of Commercial Street and Hanbury), as both are in high interest areas. On the JtR map project (found here), you can see their locations. There are a few other Beer Shops, which I think are pubs as well and not just "take aways", in the general area as well. If the police were to do a search, the recommendation would be to check out all of the pubs starting centrally (say the Queen's Head or 10 Bells) and working outwards to some distance say within a 5 minute walk. The idea being that JtR spending his evening drinking, and then go on the prowl in search of a victim after the pub had closed. He wouldn't find a victim every time, of course, and may find victims in other ways as well, but one would be considering the idea that he makes many more "scouting" trips than he does successful victim finding. So the police would want to become familiar with those who regularly stay to closing (or close to), and then are again spotted walking around the area rather than going on home. That's the sort of behaviour one might look for, particularly if the individual was seen to chat to woman during his nightly excursions.

          Of course, the "high interest area", might also reflect the commonality of the victim's residences, which were all generally in that area, rather than JtR himself. That needs to be kept in mind, but regardless, that area would be a good place to keep watch to see if anyone appears to be doing a "circuit" at night (someone seen walking through the area multiple times late at night, even if they didn't start from one of the pubs, would also be of interest to keep an eye on).

          As I say, this type of information is about suggesting where to look, it doesn't tell you what to look for! That's the detective's job. Part of it would be to try and work out why a particular area might be of high interest (just like trying to determine if a spouse has a motive; knowing person X is the spouse, and that a spouse is a person high on the "interest list", doesn't tell you why they might have committed a murder - doesn't give you a motive, that's for the police investigation to determine if there is or is not a motive, etc).

          So, my suggestion would be to have undercover detectives watch the pubs in the area and as closing approaches, watch any single men leaving the pub who then appear to go on patrol rather than just "go home". That would entail following them, obviously. Others could be put on fixed point observations, with the idea of seeing if anyone seems to keep passing by (Commercial Street would be a good place for this). Again, the idea is if Person X keeps passing by at semi-regular intervals, then they would appear to be doing some sort of search pattern, particularly if that person always passes going in the same direction (suggesting they are doing a "circular" path). Such an individual would also be worthy of following, to take note of what they are doing, and so forth.

          - Jeff

          Comment


          • #20
            Originally posted by JeffHamm View Post

            The Queen's Head would be one to focus on, but not the only one. The Britania Pub (East end of Dorset Street) and The Ten Bells are also in the area of interest, and I wouldn't overlook The Horn of Plenty (west end of Dorset Street) or the Golden Heart Pub (corner of Commercial Street and Hanbury), as both are in high interest areas. On the JtR map project (found here), you can see their locations. There are a few other Beer Shops, which I think are pubs as well and not just "take aways", in the general area as well. If the police were to do a search, the recommendation would be to check out all of the pubs starting centrally (say the Queen's Head or 10 Bells) and working outwards to some distance say within a 5 minute walk. The idea being that JtR spending his evening drinking, and then go on the prowl in search of a victim after the pub had closed. He wouldn't find a victim every time, of course, and may find victims in other ways as well, but one would be considering the idea that he makes many more "scouting" trips than he does successful victim finding. So the police would want to become familiar with those who regularly stay to closing (or close to), and then are again spotted walking around the area rather than going on home. That's the sort of behaviour one might look for, particularly if the individual was seen to chat to woman during his nightly excursions.

            Of course, the "high interest area", might also reflect the commonality of the victim's residences, which were all generally in that area, rather than JtR himself. That needs to be kept in mind, but regardless, that area would be a good place to keep watch to see if anyone appears to be doing a "circuit" at night (someone seen walking through the area multiple times late at night, even if they didn't start from one of the pubs, would also be of interest to keep an eye on).

            As I say, this type of information is about suggesting where to look, it doesn't tell you what to look for! That's the detective's job. Part of it would be to try and work out why a particular area might be of high interest (just like trying to determine if a spouse has a motive; knowing person X is the spouse, and that a spouse is a person high on the "interest list", doesn't tell you why they might have committed a murder - doesn't give you a motive, that's for the police investigation to determine if there is or is not a motive, etc).

            So, my suggestion would be to have undercover detectives watch the pubs in the area and as closing approaches, watch any single men leaving the pub who then appear to go on patrol rather than just "go home". That would entail following them, obviously. Others could be put on fixed point observations, with the idea of seeing if anyone seems to keep passing by (Commercial Street would be a good place for this). Again, the idea is if Person X keeps passing by at semi-regular intervals, then they would appear to be doing some sort of search pattern, particularly if that person always passes going in the same direction (suggesting they are doing a "circular" path). Such an individual would also be worthy of following, to take note of what they are doing, and so forth.

            - Jeff
            Jeff, exceptional post and very enlightening.

            Do you think that the police/detectives/undercover officers at the time were focused on looking for precisely what you describe above, but with a degree of bias; perhaps looking for your stereotypical dodgy-looking man lurking in the shadows, when the killer may have looked and presented themselves as 'ordinary' and thus eluded the police on that very basis?
            In other words, could bias/prejudice have played a part in the killer having not been caught?

            What you describe in your message is brilliant and makes complete logical common sense, but I wonder if the police at the time were that savvy when it came to their application.

            In the lead-up to the murders of Smith, Tabram, Stride, Mylett and possibly Kelly, there is evidence to suggest that there was more than one man involved in the killings.

            That's roughly half of all the murders that have been arguably attributed to the Ripper in one way or another; and 2 of the 5 Canonical victims.

            Perhaps the police spent too much time looking for a lone wolf, when there were multiple men involved?


            RD
            "Great minds, don't think alike"

            Comment


            • #21
              Originally posted by The Rookie Detective View Post

              Jeff, exceptional post and very enlightening.

              Do you think that the police/detectives/undercover officers at the time were focused on looking for precisely what you describe above, but with a degree of bias; perhaps looking for your stereotypical dodgy-looking man lurking in the shadows, when the killer may have looked and presented themselves as 'ordinary' and thus eluded the police on that very basis?
              In other words, could bias/prejudice have played a part in the killer having not been caught?

              What you describe in your message is brilliant and makes complete logical common sense, but I wonder if the police at the time were that savvy when it came to their application.

              In the lead-up to the murders of Smith, Tabram, Stride, Mylett and possibly Kelly, there is evidence to suggest that there was more than one man involved in the killings.

              That's roughly half of all the murders that have been arguably attributed to the Ripper in one way or another; and 2 of the 5 Canonical victims.

              Perhaps the police spent too much time looking for a lone wolf, when there were multiple men involved?


              RD
              I can't answer much of that. We know the police did house to house questioning, but we don't know what they asked, what they did, etc. We know they had undercover men on the streets, but we don't know what they were told to look for. Without those sorts of details, we cannot evaluate their methods with respect to whether or not they were biased in what they were looking for. It is, of course, possible they were, but it is of course possible they were not - so take your pick if you wish to gamble, or accept that we can't answer that at present even though we agree it is an important question.

              I'm aware of two possible individuals in the Stride murder (Broad Shoulders and Pipeman), the impression one gets from the police view is that Pipeman was not associated with Broad Shoulders (their connection comes from Schwartz's initial idea that B.S. shouted "Lipski" to Pipeman as a sort of "heads up" call - which is why the police were tracking down all the Lipski families in the area, just in case Schwartz was correct even though they figured Lipski was actually shouted at Schwartz himself - that to me is a sign of good police work, follow up on all leads, even the ones your own opinion doesn't favour; see the Yorkshire Ripper case for an example of why failing to do this is a bad thing!!! The police of 1888 did that, at least, a bit better).

              I'm not really aware of anything that suggests two people might have been involved in the Kelly murder though? I know there was a "pardon" issued following her murder, but I think the idea was to pardon anyone involved "after the fact", not someone directly involved in the murder (as in, "Little Willy came home that night. He was covered in blood, carrying this heart he said he got from the butcher, but it wasn't no cow heart. I helped him wash up, got rid of his bloody clothes that he said the heart dripped on - but I had my doubts, yes sir, I had my doubts - and as hearing of the awful murder the next day, it upset me so, I threw the heart in the Thames. We then took Little Willy to the country side to get the air, and are keeping a close watch on him and he's so much better. I rather think I just over reacted by coming here .... that sort of thing, a pardon for family members who might have helped after the fact, and after hearing of the murders, thought there's something not quite right with "Little Willy", but were worried that they may done something themselves that would get them in trouble.

              - Jeff

              Comment


              • #22
                Originally posted by JeffHamm View Post

                The Queen's Head would be one to focus on, but not the only one. The Britania Pub (East end of Dorset Street) and The Ten Bells are also in the area of interest, and I wouldn't overlook The Horn of Plenty (west end of Dorset Street) or the Golden Heart Pub (corner of Commercial Street and Hanbury), as both are in high interest areas.
                Hi Jeff,

                I'd add the Frying Pan (corner Thrawl St and Brick Lane) and the Princess Alice (corner Commercial St and Wentworth St) to that list.

                Best regards, George
                Much that once was is lost, for none now live who remember it.​ - LOTR

                All those moments will be lost in time, like tears in rain. - Bladerunner

                ​Disagreeing doesn't have to be disagreeable - Jeff Hamm

                Comment


                • #23
                  Originally posted by GBinOz View Post

                  Hi Jeff,

                  I'd add the Frying Pan (corner Thrawl St and Brick Lane) and the Princess Alice (corner Commercial St and Wentworth St) to that list.

                  Best regards, George
                  Yes, good call. I admit, I did only a cursory scan, as I think it might be a bit late to set up surveillance.

                  - Jeff

                  Comment


                  • #24
                    The killer will likely have frequented all those public and beer houses in the locality at some point; they're probably all relevant in some way.

                    In addition, I would also include Coffee Houses.


                    RD
                    "Great minds, don't think alike"

                    Comment


                    • #25
                      Originally posted by The Rookie Detective View Post
                      The killer will likely have frequented all those public and beer houses in the locality at some point; they're probably all relevant in some way.

                      In addition, I would also include Coffee Houses.


                      RD
                      Sure, if the coffee houses stayed open that late; I know they were local social hot spots, so maybe they did, but I'm not all that familiar with them or how they "worked". Observers on the street are a good way to avoid picking one type of establishment over another, but having people in the pubs, to get a feel "for the locals" is also a reasonable approach (particularly given the times of the offenses are after closing time - although most are well after, such as Nichols, Chapman (no matter if one favours an early or late ToD, both are well after 12:30, which I believe was the official closing time), and Kelly. Eddowes is a bit late, but as she's the 2nd of the double event, and Stride's murder isn't too far removed from closing time, Eddowes murder may simply reflect the "delay" involved with Stride's murder. Of course, if Stride isn't actually a JtR victim, then that still puts Eddowes after closing time, and certainly no further than either Nichols or Chapman.

                      If Chapman was murdered much later, closer to 5:20ish, then it would suggest JtR was just heading out I would think. That would tend to suggest that JtR lived somewhat near #29. By somewhat, I just mean closer to that location than others, save perhaps Miller's Court, as it is just round the corner really, but if I had to say, I would think within a 5 minute walk. The idea being that he's probably only just headed out, "got lucky", and also if the murder was at 5;20, it means he's ok with rushing home to clean up - so must feel it's only a short dash home type thing. This is all highly speculative stuff, and is the sort of thing one would then actually investigate to see if this line of thinking gets us anywhere.

                      - Jeff

                      Comment


                      • #26
                        Originally posted by The Rookie Detective View Post

                        The killer will likely have frequented all those public and beer houses in the locality at some point; they're probably all relevant in some way.
                        I wouldn't go along with this. Quite possible but in terms of likelihood I'd say it's open to debate.

                        It would be interesting to know the percentage of serial killers who sought out victims in drinking establishments and/or socialised in the area.

                        I can think of a few who did, but I can think of many more who didn't.

                        I can't find any statistics, but my inclination is to say that the vast majority of serial killers who murder women, i.e. similar crimes to the WM; pick up sex workers on the street, pick up hitchhikers, break into people's homes or drive around looking for victims in the street.

                        Comment


                        • #27
                          I posted this on the "Stuart Kind" thread, but I'll also post it here:

                          "There are no less than 146 registered lodging-houses, with a number of beds exceeding 6,000. Of these 1,150 are in Flower and Dean-street alone, and nearly 700 in Dorset-street. Some of the houses contain as few as four beds, whilst others have as many as 350."

                          If Jack was randomly selecting women he found walking the street, as far apart as Mitre Square, Dutfields yard, Buck's Row and Hanbury St, what would be the odds that they would all be living in the Flower and Dean/Dorset street lodging houses, which comprised less than a third of the total. What additional effect would there be on those odds that the profiler programs show the same areas as hot-spots for Jack's anchor points.
                          Much that once was is lost, for none now live who remember it.​ - LOTR

                          All those moments will be lost in time, like tears in rain. - Bladerunner

                          ​Disagreeing doesn't have to be disagreeable - Jeff Hamm

                          Comment


                          • #28
                            Originally posted by GBinOz View Post
                            I posted this on the "Stuart Kind" thread, but I'll also post it here:

                            "There are no less than 146 registered lodging-houses, with a number of beds exceeding 6,000. Of these 1,150 are in Flower and Dean-street alone, and nearly 700 in Dorset-street. Some of the houses contain as few as four beds, whilst others have as many as 350."

                            If Jack was randomly selecting women he found walking the street, as far apart as Mitre Square, Dutfields yard, Buck's Row and Hanbury St, what would be the odds that they would all be living in the Flower and Dean/Dorset street lodging houses, which comprised less than a third of the total. What additional effect would there be on those odds that the profiler programs show the same areas as hot-spots for Jack's anchor points.
                            I initiated another thread a few months ago "Lodging House Link" in an attempt to highlight the fact that ALL of the Canonical 5 PLUS several other potential Ripper victims can all be linked to lodging houses in just 3 streets...2 of those streets you mention above.

                            It is refreshing to see that you have also highlighted the fact independently. That must indicate that there IS a "Lodging House Link"

                            Please check out the thread I started. The thread stalled for the same reason that most threads stall, but I am currently in the process of analyzing the links between the victims and the lodging houses they frequented; because there is undoubtedly a link between them.

                            My theory being that the murder sites themselves are only a small piece of the puzzle; whereas the bigger piece of the jigsaw lies in the lodging houses and the places each victim lived BEFORE they were murdered.

                            Great post George as always


                            RD
                            Last edited by The Rookie Detective; 11-23-2023, 01:31 AM.
                            "Great minds, don't think alike"

                            Comment


                            • #29
                              Originally posted by GBinOz View Post
                              I posted this on the "Stuart Kind" thread, but I'll also post it here:

                              "There are no less than 146 registered lodging-houses, with a number of beds exceeding 6,000. Of these 1,150 are in Flower and Dean-street alone, and nearly 700 in Dorset-street. Some of the houses contain as few as four beds, whilst others have as many as 350."

                              If Jack was randomly selecting women he found walking the street, as far apart as Mitre Square, Dutfields yard, Buck's Row and Hanbury St, what would be the odds that they would all be living in the Flower and Dean/Dorset street lodging houses, which comprised less than a third of the total. What additional effect would there be on those odds that the profiler programs show the same areas as hot-spots for Jack's anchor points.
                              Hi George,

                              I replied to this in the other thread, but the odds are a bit tricky if the distribution of men and woman wasn't uniform. If, for example, the area around Flower and Dean had a higher proportion of women (say, some doss houses were primarily woman, or perhaps other areas at least had fewer woman - the idea being the woman tended to cluster for comradeship and safety, etc) then it might be that the vast majority of the woman living in Doss houses lived in that region, making the odds high.

                              I can't recall, but if, for example, we saw Tabram, Coles, and McKenzie were also of that area, then it might suggest that was simply the area where the most woman were concentrated.

                              - Jeff

                              Comment


                              • #30
                                Originally posted by The Rookie Detective View Post

                                My theory being that the murder sites themselves are only a small piece of the puzzle; whereas the bigger piece of the jigsaw lies in the lodging houses and the places each victim lived BEFORE they were murdered.

                                Great post George as always


                                RD
                                Hi RD,

                                Thank you. You are too kind.

                                Looking at only the murder sites is somewhat akin to looking at the end of a story rather than starting at the beginning.

                                I have addressed some of your points on the "Stuart Kind" thread so rather than repeat them I'll refer you to my post # 36 on that thread.

                                Cheers, George

                                Much that once was is lost, for none now live who remember it.​ - LOTR

                                All those moments will be lost in time, like tears in rain. - Bladerunner

                                ​Disagreeing doesn't have to be disagreeable - Jeff Hamm

                                Comment

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