The most important rule of self defense - Statistics

[Tennessee Gentleman]

Where I see the statistics thing falling apart is when someone says: "well studies show that the odds are if you are robbed you won't be harmed, so don't resist." or "don't engage in a gunfight ever because cops only hit 20% of the time" or "there is no need to carry because the UCR shows odds that you won't be attacked" and so on. I will assess the situation as I see it then and take action based on what I see and the training and experience I have at that time and not based on odds from a study some academic quotes, which could be wrong.

 

[Brian Pfleuger]

I will assess the situation as I see it then and take action based on what I see and the training and experience I have at that time and not based on odds from a study some academic quotes, which could be wrong.

You're absolutely right. On the flip side, it's equally wrong to suggest an automatic "SHOOT" response to any given situation. Such responses are based on an equally deceptive and inaccurate application of statistics.

 

[psyfly]

A few minor observations about statistics that I have found helpful.

1. Statistics are about counting numbers (most often LARGE numbers) of events.

2. An event cannot be counted as a part of a statistic until the event is over.

3. There are no statistics that can tell us anything really useful about a single event that hasn’t even happened yet.

4. From a personal perspective, it doesn’t much matter if the odds are two to one or 2 million to one……..if you happen to be the one .

I like to be prepared for the possibility, however small, that I will be the one.

Best,

Will

 

[David Armstrong]

I like to be prepared for the possibility, however small, that I will be the one.

Sure, we'd all like that. However, it isn't possible, so we need to decide what possibilities we can prepare for and what possibilities we should prepare for. Is it better to prepare for a BG attacking you in a parking lot or to prepare for a tiger leaping through your living room window and trying to eat you? Both are possible.

3. There are no statistics that can tell us anything really useful about a single event that hasn’t even happened yet.

Sure there are. For example, statistics can tell us that you are probably going to be better off in a vehicle accident if you are using your seat belt than if you are not using it.

 

[Tennessee Gentleman]

On the flip side, it's equally wrong to suggest an automatic "SHOOT" response to any given situation. Such responses are based on an equally deceptive and inaccurate application of statistics.

peetza, we have a very serious case of agreement here.

 

[psyfly]

Sure there are. For example, statistics can tell us that you are probably going to be better off in a vehicle accident if you are using your seat belt than if you are not using it.

I'm not convinced.

One, the operative word in your response here, unfortunately for certainty, is "probably".

Two, okay, I was using a bit of hyperbole, statistics do identify trends which can be useful to us in making decisions. But they cannot, by their nature, tell us anything predictive about a single individual or event.

For example, I have a good friend who is alive today because she was sitting on her seatbelt during the accident. Had she been wearing it, she would not have survived. Does this lead me to not wear my seatbelt? Of course not, after all, her statistic has already been counted . But it does help illustrate the limitations of statistical methods in individual prediction.

Best,

Will

 

[Brian Pfleuger]

peetza, we have a very serious case of agreement here.

What are we supposed to argue about then?

 

[David Armstrong]

One, the operative word in your response here, unfortunately for certainty, is "probably".

Of course, that is what predictive stats deal with, probability. They allow us to understand the dynamics of a situation. They let us know what will "probably" happen so we can build a response that deals with the probability of that response working. For example, in a murder situation, we know with a high degree of likelihood that going along with the killer's wishes is is probably going to result in you being killed, just like we know that in an armed robbery situation going along with the robber's wishes will probably minimize your loss and danger. You can never be certain, but you can know what tends to work out best and start from there.

But they cannot, by their nature, tell us anything predictive about a single individual or event.

Sure they do. I can predict that you will not live to be 300 years old. I can predict that in an NBA basketball game that each team will score at least one goal.

For example, I have a good friend who is alive today because she was sitting on her seatbelt during the accident. Had she been wearing it, she would not have survived.

That is an assumption, unless you have replicated the accident with her wearing the belt and she did die.

But it does help illustrate the limitations of statistical methods in individual prediction.

Of course there are limits, but that does not mean you cannot predict at all or without any level of certainty. There will always be some degree of uncertainty, but the lower one gets that the better.

 

[Tennessee Gentleman]

What are we supposed to argue about then?

Oh, I am sure we will find something later on

There will always be some degree of uncertainty

Which is why using statistics (and we haven't even discussed context or bias) are pretty useless in these types of self-defense discussions.

 

[ZeSpectre]

Sorry, I'm going to have to disagree with the OP's premise right from the start.

Self defense, tactics, and training have nothing to do with statistics.

It's not about the odds of something happening, it's all about the consequences that happen if you aren't prepared.

 

[Glenn E. Meyer]

I am totally confused by this discussion and the use of the term 'statistics'.

There are descriptive statistics and inferential statistics. To describe and predict. People do act as intuitive scientists and make predictions.

One may not explicitly worry if one's wife will dismember them but one does usually have health insurance to pay for the cost of injuries. One may not engage in adulterous behavior or spousal abuse because one predicts that this usually doesn't end well. That's making a prediction.

Most of us don't wear body armor all the time as compared to officers. Most of us don't walk around with M4s as compared to soldiers in Iraq or Afghanistan. That's because we have a feel for the probabilities of a civilian in our environments needing either.

Formal statistics just quantify and test such informal views.

On fora like this, the statistics arguments usually center about:

1. How many mags do you carry?
2. Do you need a BUG?
3. Don't practice beyond 3 inches as gun fights are close up.

or something like that.

Then folks carry on about extreme cases - well, statistic methods are based on predicting the likelihood of such an outcome and the likelihood of an error if you don't take such an action. However, anyone with stat training knows that the cutoff and decision points for an action based on distributions is a subjective decision.

So when you say that you will carry one extra mag, even though it is rarely used, you are making a choice based on your view of the risk of not being ready for an extreme case. That is not outside our statistical methodologies. We evaluate the cutoffs based on such outcomes.

I see little here that does negate statistical methodolgies if correctly applied and understood. It is usually that someone wants to make a decision based solely on central tendency where these arguments go awry.

Well, a gun fight only has 3 shots on the average, thus I NEVER need more that a J frame with 5 - it's the implicit never which makes those kind of comments baloney.

I think we are smart enough to get beyond that. You plan for extremes if the risk of being in one is so horrendous that you take the inconvenience of planning for it. But these analyses are second nature if you really use statistics as they were designed.

 

[David Armstrong]

It's not about the odds of something happening, it's all about the consequences that happen if you aren't prepared.

How do you decide what to prepare for if you don't know what the threats are and what works to stop them? That info comes from statistics. How do you know what training works, and what tactics work? That information comes from statistics.

 

[ZeSpectre]

How do you decide what to prepare for if you don't know what the threats are and what works to stop them? That info comes from statistics. How do you know what training works, and what tactics work? That information comes from statistics.

I don't know about you but I don't prepare for trouble based on the statistical probability of what might happen to me. I take into account the general categories of bad things that happen (regardless of the "odds" of them actually happening) and try to work with broad spectrum tools and techniques that stand a chance of working under the widest variety of conditions.

I will agree that finding effective countermeasures is enhanced by a study of the statistics regarding success.

 

[Brian Pfleuger]

It's not about the odds of something happening, it's all about the consequences that happen if you aren't prepared.

I made a song about that in the "other" thread. You make plans based on BOTH probability AND severity. A meteor crashing into your house would be VERY severe, yet you (I hope) aren't preparing for it. It's the same as carrying a spare mag or driving fast or not wearing a seatbelt. If you planned based entirely on severity you would, well for one thing you'd never get out of bed, but for another thing, you'd feel compelled to walk around in body armor with the M4 mentioned by Glenn, driving an armored car with RPGs in the trunk.

You have to draw the line SOMEWHERE. That line is drawn based almost entirely on ODDS, not severity.

 

[ZeSpectre]

You make plans based on BOTH probability AND severity

Not really or I wouldn't bother with a firearm at all. The odds of me ever needing one are pretty damned small and the inconvenience of owning and carrying one is pretty big. However the severity of a situation where I'd actually need a gun and the consequences of not having one at that critical time, weigh far more heavily on my mind than the odds.

A meteor crashing into your house would be...

of no concern since there is no preparation for such an event that I'm capable of carrying out.

 

[Brian Pfleuger]

Do you prepare for a plane crash in your neighborhood? A Mumbai situation? A truck driving through your house? An escaped elephant from the zoo? How about being in the middle of the North Hollywood Shootout?


Bottom Line: If you don't go about your life looking like a Marine in Baghdad then you're making your decisions based on severity and odds, MOSTLY odds because the most severe scenarios are essentially ignored.

 

[Glenn E. Meyer]

You have to take into account the odds when you look at severity.

There is a possibility that some quantum event will port me into another dimension where I will need a M4 and a plan to start a new civilization. If I didn't have such plans then the outcomes are severe. But this is unlikely and thus I leave my plans for a new civilization at home. When you say you plan for severity - that is because your realize that there is a small likelihood of the event but if that occurs it will be severe. But you don't plan for events that don't have that small but severe package.

When someone says they don't take into account the odds, that's just not true. We predict possible outcomes on most things we do.

Again, rational decision making takes into account the odds and the outcomes.

 

[Rich Miranda]

...you'll get unexpected results in the end that are considered 'impossible' by any statistical analysis

The odds of something occurring fall into a 'likelihood range'. But if something did actually occur, it was never 'impossible' that it could have.

 

[Tennessee Gentleman]

Not really or I wouldn't bother with a firearm at all. The odds of me ever needing one are pretty damned small and the inconvenience of owning and carrying one is pretty big. However the severity of a situation where I'd actually need a gun and the consequences of not having one at that critical time, weigh far more heavily on my mind than the odds.

Common sense again. I agree odds aren't in that equation or you wouldn't carry.

 

[Wuchak]

In the most basic form of risk analysis you look at risk and severity and use them together to identify the steps you should take to either mitigate the risk or prepare for the occurrence.

Basically it's the following steps.
• Identify Risk: “What could go wrong?”
• Analyse Risk: “What is the likelihood of this happening, and what’s the impact?”
• Plan Risk Response: “What do I need to do about it?” (This is what I can do to prevent the risk from occurring.)
• Monitor and Control Risk: “How is the risk changing?” (is it growing, lessening, or staying the same over time)
• Execute Contingency Plan: “What do we do if the risk happens anyway?” (this is what I do if my plan to prevent the risk didn't work or if it is something I have no ability to control)

It's very useful to list the risks and then give a weighted value by multiplying the the likelihood and the impact to get a risk factor. I like to use a 1 - 3 - 5 scale. Where for likely-hood 1 is not likely to occur, 3 is somewhat likely to occur, 5 is almost certainly going to occur. For severity 1 is not severe at all, 3 - somewhat severe, 5 - severe.

Those items with the highest risk factors should be addressed first. In many cases there is nothing you can do to change the likely-hood of an event, you can only have a contingency plan. For example if I have an office building in the midwest there is nothing I can do to prevent a tornado from hitting it but I should have a plan in place for what I will do if one does hit it.

Statistics come in when I'm looking at establishing what bucket to classify a risk into. Statistics are great for predicting the behavior of groups of a type of event but not individual occurrences. They let me make some very educated guesses about an individual occurrence but the larger the group I am describing the more accurate my prediction can be. For example (and I'm making up the numbers) if analysis shows that out of 1,000,000 armed assaults where the victim was armed they only had to actually shoot the aggressor 20% of the time and that only 1% of those shootings was fatal I cannot tell you which percentage an armed assault you are involved in will fall into. What I could tell you is that if you were involved in an armed assault you are 4x more likely to not have to shoot as to shoot and you are very unlikely to kill the attacker if you do have to shoot.