Probability of Double Event

[Fisherman]

Pinkerton:

"I believe I am in the majority opinion in this regard."

Enjoy it while it lasts, Pinkerton!

"Yeah I remember Sam. A nice fellow but a little over the top"

Then you don´t remember Sam, Pinkerton - trust me.

"I don't think this was Resendez. Would be curious to see who you are referring to though."

Mmm, could be someone else. I have looked for it with no success before, but I will give it another try. I am quite certain about the details, though.

"The Ripper murders as you know did not involve the entire East End--only a small section of it. Overcrowding also existed in Bethnal Green, Stepney, Shoreditch and other places in the East End where the murders did NOT occur. "

Yes, and in Hong Kong too - but the gist of the matter is that we must weigh in the density of population before we cry "Ripper", Pinkerton. It´s math´s.

"This is not exactly true. Of the cases I have come across a razor was often used"

Blade, Pinkerton. Cutting. I´ll merrily rephrase if I am too inexact. The message I was trying to convey is that blade violence perpetrated against women of questionable moral was around in quantities large enough for us to realize that the earth will not be flattened if you are wrong on the Stride killing.

"Copycat crimes I can understand."

Perhaps so, but you did not learn that from Eddowes and Stride, for they are anything but copycat murders. They are distinctly, definitely,and obviously different in character. One of them - and I think you know which - had the looks of a dreary and ordinary blade killing, whereas the other told the story of a mutilating madman.

"The three scenarios I offered for there being two killers stated earlier in the thread cover every possibility. Collusion (two killers working in tandem), Ripper acts on hearing of other murder, and two murders committed coincidentally by two different killers. I believe only the first two fall into the realm of possibility, but are still extremely unlikely."

Actually, I have just pointed out - to deaf ears apparently - that Tabram, Coles and MacKenzie took the odds to 1/365. Adding Millwood, Wilson and Smith, we end up with 1/182,5. Both these figures speak of a mathematical possibility, Pinkerton, not an IMpossibility.
After that, we can add all other incidents where a prostitute laid eyes on a knife, and the odds will fall further and further.

But that does not matter to you, does it? You just wrote that this scenario did not even fall into the realm of possibility.
Well, you were wrong. Chances are that people will think that you are blind on one eye, Pinkerton. Or that you are, shall we say ... a little over the top.

The best,
Fisherman

[Rubyretro]

"Well then, old man, give us half a pound of the black ones".

Packer was 57 in 1888. In the world of the common East-ender, that equated to being an old man.

Someone from the East End may very well refer (even today) to their 'old man' or old lady' regardless of age. I see that the Rolling Stones used this expression in the '60s (and how old were they ??) and Mick was only a Mockney.

However, I do agree that 57 was old in 1888.

I think that JtR killed Liz though.

[Fisherman]

Ruby:

"Someone from the East End may very well refer (even today) to their 'old man' or old lady' regardless of age."

But would that not mainly be in a friendly conversation with somebody you knew beforehand? I think the way this expression was used back in 1888 is not the exact same as it is now.

Anyway, this is not the core issue here, but instead that 57 WAS old. And Marshall, at 52, would have been getting on too; he certainly would not have been middle-aged any longer, in the eyes of his contemporaries - he would have been past middle age.

"I think that JtR killed Liz though."

...which is fine, and a perfectly legitimate stance, Ruby. It´s when Pinkerton suggests that recognizing the possibility of another killer is to move beyond the realms of probability that I protest.

The best,
Fisherman

[Fisherman]

On the point of which case it was where four bodies were found dumped by a railway track, but only three were related to the same serial killer: that was the John Eric Armstrong case. It was in Detroit, and all of the bodies found were in different stages of decomposition.

The best,
Fisherman

[lynn cates]

double event defined

Hello Fish et al. I am curious about what, precisely, is meant by a double event. It seems it can be defined in 2 ways.

1. It could refer to Liz and Kate being killed by the same hand.

2. It could refer to Liz and Kate being killed by different hands but for a same or similar purpose.

Regarding # 2, I recall the letter by Sir Charles from October 12, where he speculates that the organisation which had them killed and the purpose for which they were killed, was the same in both their cases. He claimed that it was obviously to discredit Jews/Socialists.

Does this theory entail a "double event" even with different hands involved?

Cheers.
LC

[macknnc]

Well for my part, I mean, (and have always meant,) Stride and Eddowes both killed by the same hand...

[Tom_Wescott]

Jon Guy, Cyber-bully

No, you were hopelessly wrong, perpetuating myths once again.

LOL, that's cute, considering I'm the only person who has bothered to published articles correcting the virtually uncountable errors made by other writers and perpetuated endless by vitriolic message board posters such as yourself. Of course, if you honestly feel I'm perpetuating myths, by all means, show me where I'm wrong. You wouldn't be the first to have tried, but you might be the first to succeed.

Yours truly,

Tom Wescott

[Fleetwood Mac]

Just one thing..I'm 60...and 30 is not "middle aged" and it wasn't 30 years ago when it applied to me, either.

Was 30 middle age in 1888? Given the shorter life spans of those days, I would have to say the answer is "possibly"

Do different people see the same person with different eyes and make different judgments about their age? Of course they do.. and they do so all the time..

With all that, I see no significant difference in the two men and would assume one man was being described twice...

Today....30 would never in a million years be described as middle aged in England.....people see 40s/50s as middle aged......but it may have been different then due to a shorter lifespan.....a quick google could be the answer. The judgement depends on the judge too of course...

Apart from that....

I would say the jury would be out as to whether they're the same man....similarities yes....but similarities you may expect as the descriptions seem fairly standard.....there is nothing that leads me to assume they're same man or rule it out......

5'5 is fairly standard for that day and height isn't easy to judge....black clothes etc etc...

I suppose it depends on what evidence you need for your beliefs as a general rule of thumb....and there simply isn't enough there for me to assume it's the same man......although I wouldn't rule it out....

On the Double Event question.....you can't divorce the pattern from these two murders when forming a view......the whole point of rationality is given what we know what else is likely to be true....and it is known that it is very rare indeed that two murderers strike within an hour of each other at roughly the same location...it is highly probable that it was the same killer given what we know of the incidence of murders.....to me that is as indisputable as anything you are likely to find in this case....or anywhere on this planet....

Oh and Chava.....your heads/tails analogy doesn't work here....as you haven't flipped a coin 49 times and they've all been heads....whereas we know that of 49 murders.....any 49 murders......at any given time......none of them have been commited by different people within an hour of each other in a similar location....unless they have been working in tandem in some politically motivated act such as a pogrom....

[Fisherman]

Fleetwod Mac:

"30 would never in a million years be described as middle aged in England.....people see 40s/50s as middle aged......but it may have been different then due to a shorter lifespan.....a quick google could be the answer."

It´s already on the thread, Mac. Just read, and you will know.

The best,
Fisherman

[Pinkerton]

"The Ripper murders as you know did not involve the entire East End--only a small section of it. Overcrowding also existed in Bethnal Green, Stepney, Shoreditch and other places in the East End where the murders did NOT occur. "

Yes, and in Hong Kong too - but the gist of the matter is that we must weigh in the density of population before we cry "Ripper", Pinkerton. It´s math´s.

I acknowledged (if you re-read my post) that Whitechapel was one of the most crowded areas did I not? However it is still only a tiny fraction of the population of London of the time. And crimes in Whitechapel represented only a tiny percentage of crimes throughout London.

"This is not exactly true. Of the cases I have come across a razor was often used"

Blade, Pinkerton. Cutting. I´ll merrily rephrase if I am too inexact. The message I was trying to convey is that blade violence perpetrated against women of questionable moral was around in quantities large enough for us to realize that the earth will not be flattened if you are wrong on the Stride killing.

I was attempting to point out that Stride and Eddowes were BOTH killed with a knife, and both had their throat cut. If you choose several murders from the Old Bailey records over the course of a year you will probably find two or three stabbed with a knife, two or three with their throats cut with a knife, one or two who had their throats cut with a razor, one or two bludgeonings, one or two strangulations, and maybe a shooting. My point being that you are making it sound like almost every woman murdered during this time would have had their throats cut with a knife. I am just saying that this isn't the case. However I admit that the "killed with a knife" is the weakest part in terms of boosting the "odds". However when you pare it with having your throat cut, the odds are boosted a bit more.

"Copycat crimes I can understand."

Perhaps so, but you did not learn that from Eddowes and Stride, for they are anything but copycat murders. They are distinctly, definitely,and obviously different in character. One of them - and I think you know which - had the looks of a dreary and ordinary blade killing, whereas the other told the story of a mutilating madman.

There are many possibilities to explain the difference in the two killings and I won't bore you with the same arguments in this regard you have heard a hundred times (interruption, motivation, etc). I would only point out that these types of murders don't have to be exactly the same in character to be from the same suspect.

I personally believe people are too hung up on the "mutilation" aspect of the killings. They are engaging in a bit of "Freudian psychology" to convince themselves that the Ripper WAS a "mutilation killer". That is what "drove him" they will claim. The problem is that if you look at many serial killers they DON'T have these "fixed" methods and "fixations" in many cases. Unfortunately this type of thinking is what lead investigators to "write off" murders of victims of various serial killers like BTK and Green River killer because a victim didn't fit the "pattern" that they convinced themselves that serial killers follow.

Most serial killers are motivated by sadism and are opportunistic in their killing. Just because some of the East End victims were mutilated and some weren't doesn't mean you make the gigantic leap that they weren't related, especially when the proximity in time and space are taken into consideration. And again, the murder of prostitutes during this time WAS NOT COMMON. I know I sound like a broken record but you would almost HAVE to believe this to think perpetrators of the Stride and Eddowes murders were two different people.

"The three scenarios I offered for there being two killers stated earlier in the thread cover every possibility. Collusion (two killers working in tandem), Ripper acts on hearing of other murder, and two murders committed coincidentally by two different killers. I believe only the first two fall into the realm of possibility, but are still extremely unlikely."

Actually, I have just pointed out - to deaf ears apparently - that Tabram, Coles and MacKenzie took the odds to 1/365. Adding Millwood, Wilson and Smith, we end up with 1/182,5. Both these figures speak of a mathematical possibility, Pinkerton, not an IMpossibility.
After that, we can add all other incidents where a prostitute laid eyes on a knife, and the odds will fall further and further.

But that does not matter to you, does it? You just wrote that this scenario did not even fall into the realm of possibility.
Well, you were wrong. Chances are that people will think that you are blind on one eye, Pinkerton. Or that you are, shall we say ... a little over the top.

There is no need to get "testy" Fisherman. We are having a friendly debate (at least I hope we are). If my language was too patronizing in my previous posts then I apologize.

As to statistics, there are 24 hours in a day, and 365 days in a year. Prostitutes represented a small percentage of women (even in the East End). Cutting the throat of someone with a knife is likely the cause of less than 50% of the murders of women. Even taking population density into consideration the area in question was very small compared to the entirety of London. And the number or prostitutes murdered in an entire year in London was relatively small. And these two women were not just killed on the same day, they were killed within AN HOUR of each other and only about a MILE apart! One doesn't need a PhD to figure out that the odds are exceedingly high. McKenzie was killed several months after the other victims. I personally think she may well have been a Ripper victim however I also think there is a chance she was not. Now had she been murdered an HOUR after another victim I think it almost certain that she WAS.

And I will repeat this challenge again. I challenge ANYONE to find a case in history even REMOTELY close to this (two prostitutes murdered within an hour and a mile of each other by two different killers). Of course this rules out "war zones", "mob violence", and "riots" needless to say.

[Trevor Marriott]

The old sugestion that the killer of Stride was disturbed keeps surfaing and giving rise to the age old suggestion that the killer was still hell bent on continuing his murder spree later that night.

However I belive that one of the doctors suggested that the time of death of Stride was much earlier thanwhen everyone belives and that she bled to death. If that be the case then she was murdered by another hand, otherwise if her death had been earlier then the killer would have had the time to mutilate her body which he clearly didnt.

Ther are those who want to beleive she was killedby the ripper who will no doubt want to disregard the doctors opinion. On the other side those who dont subscribe to her being killed by the same hand as Eddowes will use it to corroborate their views.

You have to remember that Whitechapel in 1888 was unique there was no other place in the country to compare with life and death there at that time, so anything is possible.

One also has to look at the wound inflicted on Stride, the way it was inflicted is so different to the others, add to that all the other major issues i.e differnet time, loctaion etc.

Balance of probability is that she was not a ripper victim and dont let Mr Wescott convince you otherwise.

[Sam Flynn]

Hello Pink

As to statistics, there are 24 hours in a day, and 365 days in a year. Prostitutes represented a small percentage of women (even in the East End).

True, but prostitutes tend to fall into the "Most Likely" category, when it comes to being roughed up on the street.

Cutting the throat of someone with a knife is likely the cause of less than 50% of the murders of women.

IS, indeed so... as in these days. But in 1888, in one of the roughest parts of London, throat-cutting would have accounted for more deaths than it does now... and more amongst those strata of society where, not only was casual prostitution more prevalent, but also the casual carrying of knives.

One doesn't need a PhD to figure out that the odds are exceedingly high.

True, but it might take a reasonable grasp of probability not to be overly fazed by apparently scary odds.

[Fleetwood Mac]

Fleetwod Mac:

"30 would never in a million years be described as middle aged in England.....people see 40s/50s as middle aged......but it may have been different then due to a shorter lifespan.....a quick google could be the answer."

It´s already on the thread, Mac. Just read, and you will know.

The best,
Fisherman

Well....if John Lennon can lie in bed for a few days for world peace......some may consider that to be an act of extreme laziness then I can skim threads for Africa.....

In your defence Fisherman.....within 30 seconds of googling.....I found this......http://www.ourwardfamily.com/victori...s.htm....seems the 'middle aged ladies maid' was on average 30-36 years old......

[Fleetwood Mac]

However I belive that one of the doctors suggested that the time of death of Stride was much earlier thanwhen everyone belives and that she bled to death. If that be the case then she was murdered by another hand, otherwise if her death had been earlier then the killer would have had the time to mutilate her body which he clearly didnt.

Not at all...there was a club full of people...some of whom testified to being outside at 12.35-40ish.

You have to remember that Whitechapel in 1888 was unique there was no other place in the country to compare with life and death there at that time, so anything is possible.

Doesn't matter a jot what 'vision' (emphasis on vision as imagination and evidence are two entirely different things and it seems a court of law places evidence in high regard) you or I conjure up. The fact remains that the killing of women on the street was unusual in Whitechapel....as per records from the Old Bailey....and two killings by two different people within an hour of each other in close proximity.....just did not happen. So the evidence tells you that actually it's highly improbable that it happened in this case. Reason: work out what is likely given what we know is true. You may find some adherents to the principle of anything is possible when you use your imagination....among the hierarchy of the former USSR.....but it doesn't wash when it comes to a murder investigation.....where evidence and reason are paramount.

If this were two different people......it would be unheard of....now considering there are a good old 60 million of us in this country....and god knows how many have lived here since 1888....it would be amazing....almost beyond the realms of imagintion...were this the one and only time such an event occurred.

One also has to look at the wound inflicted on Stride, the way it was inflicted is so different to the others, add to that all the other major issues i.e differnet time, loctaion etc.

Except JTR wasn't in control of all factors......let's say he'd have actually gone out with the express purpose of committing a series of murders in exactly the same fashion....it would have been difficult to achieve...given the various things that could come up unexpectedly!

[Sam Flynn]

Except JTR wasn't in control of all factors...

Quite correct, Mac. However, he had previously demonstrated, and would subsequently show, the capability of quickly cutting a throat to a considerable extent - in length and depth - with one sweep of a knife, to produce a rapid and significant loss of blood. These features are wholly absent from the Stride murder.