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# Maths And Self-Defence: Does My Formula Make Mathematical Sense?

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Hi guys,

I don't have a strong maths background so hoping for some feedback on the way I think about self-defence which can be summed out as follows:

I = P(A) + P(T) + P(D)

Where:

I = probability of not being Injured/killed from attack

P(A) = probability of successful attack in a situation where you are paying Attention to what is going on around you.

P(T) = probability of successful attack depending on that particular time of day.

P(D) = probability of successful attack given you are a competent MMA fighter.

So I am thinking of using the formula like the drake equation (predicts probability of aliens based on assumed probabilities). I don't know for sure what the probability of P(A), P(T), and P(D) is, but I would like to think I can use the formula to help understand and explain the relationship of the components of the formula.

Some points of confusion

1. If each component was 0.4, then the overall probability would come out to be 1.2 - how can that be? That would suggest you cannot ever be injured or killed in an attack.

2. Can such a formula really be of any use given that there are so many variables? I mean we could also add in P(N) to indicate the probability of attack in the specific area of town you are in. Or P© to indicate probability of attack in a carpark. Can such a formula be used without specifying every single variable?

Again, just to emphasis. I am not looking to be able to calculate my exact probability of being successfully attacked. I am more just looking to be able to plug in some numbers based on my subjective views to see conclusion logically follows from those views.

So for examples, I might wonder how likely I am to be successfully attacked if P(A) = 0.01 and P(T) = 0.001 and P(D) = 0.1. It would be good to know the conclusion that logically follows.

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P(I) - probability of intuition

P(S) - probability of strength

P(s) - probability of speed over the opponent

... Are some other examples

Edited by Dubbelosix
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I suppose also the probability of ”mind ****" through the jibes, the hustling we call it in chess

P(M)

Edited by Dubbelosix
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So long as you take more than one system you can always add.... But hear out, so long as those individuals are underquoted as being synonymous in all theoretical grounds. This is why wecan addmosy galaxies together to eatinate the rough life giving properties through the Drake equation,its because idealistically-spea,king, galaxies are more or less identical dust particles on the cosmic scale.

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Adding an ensemble is fine but we also multiply to find the square of probabilities as well.

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Adding an ensemble is fine but we also multiply to find the square of probabilities as well.

Can you clarify this?

P(I) - probability of intuition

P(S) - probability of strength

P(s) - probability of speed over the opponent

... Are some other examples

Thanks, but i am trying to understand if the maths actually makes logical sense. I.e. does it actually have any value without having all the components (which seem infinite).

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Hi guys,

I don't have a strong maths background so hoping for some feedback on the way I think about self-defence which can be summed out as follows:

I = P(A) + P(T) + P(D)

Where:

I = probability of not being Injured/killed from attack

P(A) = probability of successful attack in a situation where you are paying Attention to what is going on around you.

P(T) = probability of successful attack depending on that particular time of day.

P(D) = probability of successful attack given you are a competent MMA fighter.

So I am thinking of using the formula like the drake equation (predicts probability of aliens based on assumed probabilities). I don't know for sure what the probability of P(A), P(T), and P(D) is, but I would like to think I can use the formula to help understand and explain the relationship of the components of the formula.

Some points of confusion

1. If each component was 0.4, then the overall probability would come out to be 1.2 - how can that be? That would suggest you cannot ever be injured or killed in an attack.

2. Can such a formula really be of any use given that there are so many variables? I mean we could also add in P(N) to indicate the probability of attack in the specific area of town you are in. Or P© to indicate probability of attack in a carpark. Can such a formula be used without specifying every single variable?

Again, just to emphasis. I am not looking to be able to calculate my exact probability of being successfully attacked. I am more just looking to be able to plug in some numbers based on my subjective views to see conclusion logically follows from those views.

So for examples, I might wonder how likely I am to be successfully attacked if P(A) = 0.01 and P(T) = 0.001 and P(D) = 0.1. It would be good to know the conclusion that logically follows.

Hi Wannabelifeguard,

This is an interesting thinking on the probability of being attacked and injured or killed. However, here are two points that I think will give you a better understanding about using mathematical probabilities.

1) The overall probability is not calculated by adding the individual probabilities, but by multiplying them, as it is in Drake equation. This is the reason for your 1st point of confusion.

2) Yes, a probability equation for being attacked can make sense. There are two ways of doing this:

One is to include each and every variable and scenario that may affect the outcome. For example, what is the probability of being injured or killed by a bomb which is thrown right in front of you? Well, if it explodes, then the probability is almost 1. But what if it doesn't? Well, to find that out, you need to find statistical data to find out what the probability is for those bombs not to explode. Or if a group of people attacks you with knives. You are running and if you make it to a metro where the doors close before they reach you, then you are safe. What is the probability for you to be in such a scenario? Well, this probability changes according to where the event happens, if there is a metro line or not, if the event happens at a particular time that the metro works, etc. etc. So, as you have noted, the variables are nearly infinite and you have to include all of them to have a statistically reasonable probability. These are about the situations where an attack has already begun. Calculating the probability of being attacked anywhere at any time is statistically impossible. Such events are almost unpredictable, because most of the time they include human decisions and they can be random. Such events are chaotic (highly unpredictable, extremely difficult and impossible beyond some limits to predict). The following video may help you understand chaotic events and scientific chaos theory and why they are almost unpredictable.

Another way, and the easy way, of calculating the probability of being attacked is to statistically analyse the past events for each place, time and situation. For example, how many attacks have taken place at a particular location? How often such events take place? What causes such events and are such reasons still available? When such events happened, what kind of people got injured or killed and where or in what kind of places. What was the number of injured or killed people at different times and situations or scenarios etc. Yes, this is also very complicated, but will give you more reliable results.

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