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Go Back   Casebook Forums > Ripper Discussions > Victims > General Victim Discussion

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  #11  
Old 03-18-2012, 05:12 PM
curious curious is offline
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Originally Posted by mic_ads View Post

Control: Behaviours displayed gaining control of the victim, including how the victim was approached.
Style: Behaviours displayed reflecting the offender's personality or personal offence style including those not necessary for the completion of the offence.
Violence: Behaviours displayed in the infliction of violence.

Once all the offence data was broken down and coded, I used a statistical program and test called Jaccard's coefficient to compare paired cases. Any similarity >.60 were retained.

Mike
Hi, Mike,
Very interesting information. And if you were in show business you would have already succeeded. I want to know more.

I'd like more details about all the categories. For instance, what behaviors were displayed to gain control of the victim.

When you mention approach, I'm guessing you mean as displayed on the body since there is no way to know whether the victim and killer had a conversation or not. Or maybe you looked at something else.

Anyway, very interesting and any more detail you are inclined to share, you'd have an appreciative audience.
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  #12  
Old 03-18-2012, 06:35 PM
mic_ads mic_ads is offline
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Quote:
Originally Posted by Cogidubnus View Post
Thanks for your detailed response. Much appreciated...can I just ask why 60% was chosen as a cut-off?

Cheers
Dave
Dave

When I was deciding the best way to analyse the cases on a pairwise basis, the best statistical test for this purpose was Jaccard's coefficient. As the aim was to follow the process of crime linkage as used in lmodern law enforcement, it was appropriate. When I was looking for an interpretation of the results, I read a paper by Dr Christian Hennig that used .60 as the lower limit.

The closer the value was to 1, the higher the degree of similarity. The scales were:
Values > .85 = a “highly stable” degree of similarity.
Values > .75 and < .85 = a “valid and stable”degree of similarity and,
Values >.60 and < .75 = an indicative degree of similarity.
Hence the cut off point of .60 or 60%.

Mike
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  #13  
Old 03-18-2012, 06:54 PM
mic_ads mic_ads is offline
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Originally Posted by K-453 View Post
mic_ads, which behaviours were compared, and which matched best?
Whilst I say that behaviours were compared, they were, but not on a like for like basis.
To dismantle the individual crimes, I initially created a chart that had the victims as columns and the offence behaviours as rows. It was a case of reading through all material compiled for each case and filling in the boxes.

In terms of the behaviours, it was broken down into areas such type of force (blunt force trauma, sharp point injury) and the degree of force (nil to extreme). There were areas to cover victimology such as clothing, activity at time, intoxication, occupation, etc. I also covered areas such such as wound pattern and weapons. There were something in the region of 50 individual behavioural characteristics. They were recorded as present or not present. So I was looking at the finer detail of the crimes to a point where it was Yes or No, was this feature present or not. I had to bear in mind that there were restrictions in the data as I was dealing with historic data and the recording of such was limited by the police at the time. However, this was a factor that anyone who examines the Whitechapel crimes has to contend with.

The offence behaviours were grouped into the three categories of Control, Style and Violence as previous papers had highlighted this as the best approach.

I used SPSS software to crunch the numbers. I did not look for which behaviour(s) matched best, as I was able to select the combination of grouped behaviours as required.

It is fair to say that whichever combination of behaviours were chosen, when the results for all combinations were compared, it highlighted a core group - the 8 victims. That was evident across the grouped behaviours. The degrees of similarity varied, which was expected as different behaviours were being compared in each analysis.

Mike
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  #14  
Old 03-18-2012, 07:10 PM
mic_ads mic_ads is offline
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Originally Posted by Sally View Post
Hi mic_ads,

Thanks very much for posting your results.

I'm sure everybody here would be interested to hear about your methodology.

Another member of this forum recently posted a link to an article written in 2005 which used profiling in an attempt to identify which of the Whitechapel Murders were Ripper victims.

http://forum.casebook.org/showthread.php?t=6422&page=29

(post 286)

It would be interesting to compare the results of this study with your own.

Do you intend to publish your study? It would be interesting to see your full analysis.

Thanks again.

Sally

I would like to publish my study. I have submitted it to the Journal of Investigative Psychology and Offender Profiling - it received a mixed review. There were positive remarks about the research and approach, but they questioned the topic as they thought JtR had been overdone. So I am happy with my methodology, my analysis and presentation of results. The study also branched into geographic profiling from the results but will probably be for another forum. There are other jounals so maybe one of these will consider it appropriate for their publication.

The study originally started out as an academic piece, but I have drafted another version, a book version that I have submitted to publishing agents. I have not received any offers yet, mind you, I have only contacted six agents.

In terms of the profiling article you mention, I have not read that one. I intentionally stayed away from profiling due to the mixed opinions on its value and results achieved. The process I chose was crime linkage which does share some characteristics with profiling but is a distinct and seperate process.

I hope that in answering other questions, I have outlined my methodology. However, if there are further questions, I'd be happy to answer them.

Mike
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  #15  
Old 03-18-2012, 07:18 PM
bolo bolo is offline
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Hi mic_ads,

thanks for sharing your interesting work with us.

What are your sources for the data of the control group? As far as I know, the official papers (inquest reports, etc.) do not go into detail on the way the perpetrator gained control over or approached his victims. I may be wrong here, though.

Regards,

Boris
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  #16  
Old 03-19-2012, 02:05 AM
Bridewell Bridewell is offline
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Quote:
Originally Posted by bolo View Post
Hi mic_ads,

thanks for sharing your interesting work with us.

What are your sources for the data of the control group? As far as I know, the official papers (inquest reports, etc.) do not go into detail on the way the perpetrator gained control over or approached his victims. I may be wrong here, though.

Regards,

Boris
Hi Bolo,

I think this is a key issue for me. One of the great unknowns of the whole affair is exactly how JtR approached his victims, particularly the later ones. What worked well with the earlier targets may have been less effective at the height of the scare. I don't see how it is possible to determine the line of approach without guesswork.

Having said that, I'm interested in the topic of this thread, because mic-ads seems to be applying (or at least trying to apply) as much objectivity as is possible in the circumstances.

Regards, Bridewell
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  #17  
Old 03-19-2012, 02:21 AM
Bridewell Bridewell is offline
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Hi, mic-ads

I've just had a look at your map. I wouldn't want to argue with the direction of travel from Mitre Square. I'm taking it that the red line, in both cases is based solely on the known start and end-points. Do you have any thoughts on why the killer (assuming Stride was a JtR murder) went west from Berner Street, but north-east from Mitre Square?
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  #18  
Old 03-19-2012, 02:53 AM
Beowulf Beowulf is offline
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Originally Posted by mic_ads View Post
Jon

The 15 victims considered were Annie Millwood, Ada Wilson, Emma Smith, Martha Tabram, Mary Ann Nichols, Annie Chapman, Elizabeth Stride, Catherine Eddowes, Mary Jane Kelly, Annie Farmer, Rose Mylett, Elizabeth Jackson, Alice McKenzie, an unknown female referred to as ‘Pinchin Street Torso’ and Frances Coles. Fairy Fay has been alluded to previously, however no details of her attack were located in records so the details were omitted from any further consideration.

Of note, in my results examining just offence behaviours that fell into the Control and Style grouping, Annie Millwood and Ada Wilson linked to each other, but no other cases. There was 70% similarity indicated.

I agree that finding common ground to start researching such matters does raise questions. What I can say is that having reviewed other approched, I took a unique route. I took each of the 15 cases, dismantled them into individual offence behaviours, that were grouped as Control, Style or Violence, that were defined as below:

Control: Behaviours displayed gaining control of the victim, including how the victim was approached.
Style: Behaviours displayed reflecting the offender's personality or personal offence style including those not necessary for the completion of the offence.
Violence: Behaviours displayed in the infliction of violence.

Once all the offence data was broken down and coded, I used a statistical program and test called Jaccard's coefficient to compare paired cases. Any similarity >.60 were retained.

Mike
What are the statistical chances of two murders with 71% similarities being done by the same person? Are there any percent studies regarding that? Or for that matter, 60%.
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  #19  
Old 03-21-2012, 11:58 PM
mic_ads mic_ads is offline
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Quote:
Originally Posted by bolo View Post
Hi mic_ads,

thanks for sharing your interesting work with us.

What are your sources for the data of the control group? As far as I know, the official papers (inquest reports, etc.) do not go into detail on the way the perpetrator gained control over or approached his victims. I may be wrong here, though.

Regards,

Boris
------
Boris

In terms of the data sources, my sources were initially considered through the casebook website, but I relied upon sources of information such as police reports and Coroner’s court transcripts, with secondary sources of mainstream publications. A number of specific offence behaviours were clearly identified from the data whilst other behaviours were established from the data through deductive and logical extrapolation.

To expand the point on the control issue, the main conclusions reached regarding approach and control was that the main method of approach undertaken by the offender was a ‘CON’ approach, where a ruse was used to get close to the victim. This fact was deduced from the testimony of witnesses who gave evidence at the inquests. Five victims working as prostitutes were approached using a ‘CON’ approach, inference given as solicited for sex by the offender posing as customer / client.

The main method of control of the victim was through the application of blunt force trauma at a minimal level in the form of bruises, pressure marks and abrasions. In the cases of Martha Tabram and Mary Jane Kelly, there was no blunt-force trauma to their bodies. Blunt-force trauma was generally followed by sharp force injury at a severe level. Sharp force injury to the neck was present on all occasions with an incised wound, in terms of throat slashing occurring seven times, except for Martha Tabram where the throat/neck was stabbed. The method of control used by the offender was considered as control-oriented force, aimed to restrict the victim’s movements with the aim of committing further acts upon the victim.

Mike

Last edited by mic_ads : 03-22-2012 at 12:01 AM. Reason: Refining answer
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  #20  
Old 03-22-2012, 12:39 AM
mic_ads mic_ads is offline
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What are the statistical chances of two murders with 71% similarities being done by the same person? Are there any percent studies regarding that? Or for that matter, 60%.

Beowulf
---------------------
Beowulf

In terms of percentage studies, I cannot help further.

What I will say, is that the percentage figures should not be considered in isolation. They are part of an analysis to assist within the crime linkage process. Any live investigation would use the results to focus lines of enquiry and evidence gathering, as any court case would rely upon evidence.

Look at it this way, there are 15 cases that have been examined. On face value, they are all females, attacks have been by a male with a knife but the level of injuries are not all the same. To find the similarities, the details of each case has been broken down into a list of offence characteristics, the finer detail and it is on this level that similarities have been looked for.

It would be reasonable to expect a degree of variation between cases committed by the same offender. The offender / victim interaction will never be the same in each case, and there are factors to consider such as mood / state of mind of the offender.

To help answer your point over the percentage significance, I have added a synopsis of the study, that shows the specific offence behavioural similarities:
(Please note, individual victims are identified through their initials)

The eight homicide victims were all white females with an average age of 38.4 years, ranging from 23 – 46 years. The females were working as prostitutes at the time of attack and except for ESt, the victims were noted as being intoxicated at the time of attack. None of the attacks were committed on Mondays or Thursdays but were commenced after midnight on their respective days. The selection of victims was white females working as prostitutes that all lived at the time of their demise in close proximity to each other, within a .009 square mile area of Whitechapel. There was nothing significant about their build or clothing. There was no data regarding the victim’s in terms of associates; it was not possible to ascertain whether the victim’s knew each other or were linked through a common element. All cases showed a heterosexual sexual practice, actions directed towards females.

The initial point of contact was primarily determined by the location of the victim when the offender decided to approach and attack the victim. There was insufficient information to determine whether the victims had regular routes or locations when they worked as prostitutes. The kill zone covered a .304 square mile area of Whitechapel with numerous streets, roads, lanes and alleyways where a victim could potentially be on any given evening. The interval between homicides potentially allowed the offender to select, observe and stalk the victim prior to making the decision to approach and attack. The consideration of victim surveillance and planned attacks as opposed to random victim selection and opportunistic attack was gauged in the context of the victim residence zone, the fact that 1,200 street prostitutes worked in the Whitechapel police division area during 1888 and the geo-forensic data locations in proximity to the victim residence zone. These combined factors support the deduction of planned attacks by the offender and observing the victims before their deaths.

The main method of approach undertaken by the offender was a ‘CON’ approach, where a ruse was used to get close to the victim. This fact was deduced from the testimony of witnesses who gave evidence at the inquests. Five victims working as prostitutes were approached using a ‘CON’ approach, inference given as solicited for sex by the offender posing as customer / client. The approach on MJK, AMc and FC was not established but considered similar based on the victim’s activity at or around the time of death (e.g. working as a prostitute).

The main method of control of the victim was through the application of blunt force trauma at a minimal level in the form of bruises, pressure marks and abrasions. In the cases of MT and MJK, there was no blunt-force trauma to their bodies. Blunt-force trauma was generally followed by sharp force injury at a severe level. Sharp force injury to the neck was present on all occasions with an incised wound, in terms of throat slashing occurring seven times, except for MT where the throat/neck was stabbed. The method of control used by the offender was considered as control-oriented force, aimed to restrict the victim’s movements with the aim of committing further acts upon the victim. There was no evidence of restraints used during any attack.

The death of the victim occurred shortly after initial contact and in six cases that went to completion, further acts at an extreme level in the form of post-mortem mutilation followed. The major organs were stabbed in the case of MT and the groin stabbed in the cases of MAN and CE. The mutilation of genetalia occurred on the six occasions where the offence went to completion. The offender eviscerated the abdomen and groin areas in three cases (AC, CE & MJK) with the viscera placed around the body. Anatomical knowledge was displayed in four cases - the attacks on AC, CE, MJK and AMc. In the six instances where the offence went to completion, the clothing of the victim was moved up to inflict the injuries. Although, the main part of the offence focused on post-mortem activity, there was no evidence of penetrative or non-penetrative sexual acts by the offender. In summary, the level of force used after contact and prior to the incident was severe on eight occasions, with the victim having her throat slashed or stabbed. The overall extent of sharp force injury was at an extreme level on six occasions and severe on two occasions, the latter relating to the interrupted cases of ESt and FC.

The bodies of each of the six victims where post-mortem mutilation took place were left in the position that they were in when the mutilation took place. On departure of the offender from the offence scene, the position of body in seven instances was left in a supine position, with the body of ESt left on its left hand side. There was no evidence of the bodies being moved or posed. The bodies were left in open locations to be discovered, except in the case of MJK who was attacked inside her residence. An amount of time would have been required to complete the post-mortem acts, inferring a high level of confidence on the part of the offender.

The attacks by the offender included stabbing, slashing, piercing or mutilation of sexual regions or other areas of the body that held significance to the offender. The weapon used to inflict the injuries in all eight cases was a knife that in the majority of instances was described as long bladed or 6-8 inches in length. The weapon belonged to the offender, was brought to and removed from the scene by the offender.

Characteristics of the offender’s idiosyncratic behaviours were post-mortem mutilations. Wound patterns indicated stab and incised wounds mainly to the chest and abdomen. There was anatomical focus to the breasts and most frequently, the groin / pubic region. In the case of CE, a kidney and the uterus were removed from the body and the heart was removed in the case of MJK. In both cases, the offender was deemed to have kept the organs. The items taken in these two cases were body parts and considered as trophies for the offender.

The offender’s knowledge of the crime scene locations and surrounding streets was deduced from the testimony of witnesses, civilian and police at the coroner’s inquests. The geo-forensic data highlighted victim residence locations within an average distance of .28 - .31 miles from a significant location for the offender. The ability of the perpetrator to avoid detection from police officers inferred a level of planning and awareness by the offender of factors such as police patrol routes / routines, police fixed points and knowledge of local streets and alleyways in order to travel at night undetected.

Mike
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