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Conditional probability
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Post by
Squishalot
Hrm. Well, the point of conditional probability is to estimate the probability of one thing given the probability of something else. Where the wikipedia page says P(A|B) that means "the probability of A, given B", or the probability that A is true if all you know is B. So the essential trouble with choosing people to frisk according to crime data is that crime data give you P(black|criminal), and what you want to decide whether to frisk someone is P(criminal|black). They're two different numbers, and knowing the former doesn't give you enough information to know the latter.
The intuitive way to explain it is to say that if someone tells you "half the muggings in this area are done by blacks and half are done by whites", in Portland that means watch out for blacks but in Detroit it means watch out for whites. The problems with using such statistics to decide whom to frisk go farther than just that, but that's the essence of what's confusing about conditional probability.
Mainly because MyTie was asking, but for anybody else who's interested as well.
To put it in numerical terms, suppose 1000 muggings occurred in each of two suburbs. 500 are done by black people, and 500 are done by white people, that is, 50% are done by black, and 50% are done by white.
Now, let's consider what the profile of these suburbs are like.
In Suburb A, we have a population of 90,000 black people, and 10,000 white people.
In Suburb B, we have a population of 30,000 black people, and 70,000 white people.
Suburb A:
We've got 500 black muggers, against 90,000 black people. That means that the average black person only has a 0.56% chance of being a mugger.
We've got 500 white muggers, against 10,000 white people. This means that the average white person has a 5% chance of being a mugger.
Suburb B:
We've got 500 black muggers, against 30,000 black people. This means that the average black person has a 1.67% chance of being a mugger.
We've got 500 white muggers, against 70,000 black people. This means that the average white person has a 0.71% chance of being a mugger.
So you see, even if 50% of events are caused by black/white people, the actual likelihood of the average person on the street being a mugger is really dependent on how many people there are living in that neighbourhood. If you have 500 muggings in a population of 10,000, that's going to be vastly different to having 500 muggings in a population of 10,000,000.
In Suburb A, you might look at the figures and say "well, half of crimes are caused by black people, so half of my checks will be black, and half will be white". But in reality, white guys in Suburb A are much more likely to be offenders than black people. The opposite occurs in Suburb B.
Post by
MyTie
This is getting, a bit ridiculous.
Let me break it down for you and fenomas.If A is more statistically likely than B to be X, and you choose A, you should be more likely to get X.This entire argument you presented is to show that if A occurs more than B, it may not mean that A is more statistically likely than B. But that is completely beside the point. The argument I make clearly states that
A is more statistically likely than B
. That much has already been verified.
A black person (A) in NYC
is
statistically more likely than a white person (B) to be a criminal (X), therefore if a black person (A) is chosen at random to be searched instead of a white person (B), it is more statistically likely that a criminal (X) will be found, than if the white guy had been searched.
Explain how this is wrong, or drop the arguments that racial profiling is ineffective, and do like the rest of the world and argue how it is unconstitutionally discriminatory, or immoral.
Post by
gnomerdon
This is wrong because you are pointing it out and generalizing offensive things. So offensive that when said, people won't take it too lightly.
Most statistics are 98% biased in the favor of the one who created it...... Some facts may be true too. These are very sensitive even if true.
What are black people to you? Animals? Probably so. That's what racial profiling is. Labeling and degrading people even before they commit the crime. That thought alone, is already racist.
Media could also play a big role. Everyday, there's always a black man stealing something or assaulting someone. Why don't the whites who do the same crime go on television? That's up to the news team to determine if they want their own kind to be ridiculed for his crime.
Being black isn't a choice. I'm sure some black people in our rich American history would have loved to be white. They won't have to worry about cops being on their back, or being slaves.
Here's how a high school black girl feels about her skin. I won't link site because I'm not sure if it has viruses or not. It's only 1 GIRL, so the sample pool is rather small to generalize here...
I hate being black..
Wow, I feel like crying just typing this. Everyday someone has to make a comment about black people. Like in my school, there was a fight between to ghetto girls at lunch. All the black people were getting involved in it and all the white people just stood and laughed and got scared, etc . I just watched in disgust. Then, when I sat down at my lunch table, a white boy that sits at my table said" Ugh, more black girls. You know, this school would be better without black people." And then him and another white boy that sat at my table started categorizing blacks.( Stealers, Poor, Ghetto, Ugly) I just wanted to cry , so I went to the bathroom at my school and started crying silently. I'm not in any of those categories! They just think just because the majority of blacks are like that in my school, all blacks are like that!(Man I'm crying now..) Most black people in my school try to act ghetto , because they think that's the way black people act. I'm actually really smart and non-ghetto and people call me an oreo. I have all a's and a B and B-, and most people say that's really rare for a black person to have those grades. That's why they say the school would be better without blacks. I also live in a nice 2 story house in a nice neighborhood, so I'm not poor like lots of people say. I hate being categorized and stereotyped. And when I walk into stores in the mall, white people just stare and look at me like they're waiting for me to steal something. I don't steal! And, I want to be a pediatrician when I grow up, but I never see black people that are pediatricians. Maybe they are nurses or something but never pediatricians. And, I'm afraid the patients are going to say in their mind" Oh no, we have a black doctor... she's not gonna help us.." Also, many white boys in my school say blacks are ugly and they would never date a black girl. They say they never see black girls with long hair like whites. And if they do, they immediately think it's a weave or wig. That brings my self esteem down. And with all this hate blacks are getting my self esteem is REALLY low. I'm SO uncomfortable in my own skin. I'm thinking about buying skin bleaching cream from Walmart today to make my skin lighter. I even thought about killing myself.. and If this black hate gets really out of hand, I might just do it..
I don't feel loved at all in this world being a black..
Some things said here are pretty subjective and narrow minded, but this is how SHE feels.
As ehonnads stated, it's more about income that determines if a person will commit a crime or not.
Since most blacks seem to be on a lower income level, you can expect more blacks to do crimes than other nationalities. But wait, generalizing that black people will commit more crimes is also a HORRIBLE thing it to say. Mexicans, asians, AND whites in the lower income level commit the same exact thing proportionately, but why do blacks take most heat? A white man robs a convenience store, he gets sent to jail. A black man robs a convenience store, the entire media community in that area knows about him, sees his picture, AND gets sent to jail for 6-7 years.
Racial profiling at the very root is pretty unethical. It may be true, but supporting and enforcing is not ethical, unless you believe most low income black people are animals and will steal anything they can't afford, and you believe ur own color is the most dominant and righteous one.
From a biological darwinismssmsmsms standpoint, most whites originated from England and other european places that had kings. England had a system of kings and nobles and everyone underneath was to serve. Anyone that challenged the king would ultimately be punished, by whatever means necessary. By being punished and killed would also mean that his genes would not pass on the next generation.
Same with asians. Anyone who didn't follow the emperor would be killed, family killed, and cousins and relatives murdered. In North Korea, a man who challenges Kim Jong iL will die, and his entire family bloodline would be exterminated. These are not random genes flowing around. They are controlled genes, in a controlled environment. And when genes are controlled, you would get offsprings that you would prefer to have in ur ultimate kingdom.
All of the genes (people) that revolts against the king are usually all exterminated if they are caught. The passive genes move on. And for thousands of years, the passive genes to obey the law has been passed down from generation to generation. That's probably why, sometimes, we may feel whites don't commit as many crimes as other races.
Let's use African americans for example. African americans are a species of humans, about 500-600 years were villagers. Some tribes fought for their land, stole, ravaged, and MANY also lived peaceful nomadic lives. The genes for revolt, fighting, stealing, and survival are still in their blood because it's only been 5-6 centuries when they've been introduced to what we're used to. Even though some slaves didn't revolt, they didn't want to instantly die from guns. There's a difference from fear from guns vs fear by spears and swords. After a while, the revolting gene would do a crime if he knows he won't be killed / hanged. Their type of breeding and mating is completely random. The more aggressive and dominant traits are passed to the next generation compared to passive ones.
Their genes were spread in a random way to promote SURVIVAL. sometimes, it would be hard to follow the supreme law even knowing they could be thrown in jail and be punished for a while. It doesn't even phase them. But who am I to say this, I'm not God. I'm just an alien looking at the despicable human race and generalizing them so that my selfish self would understand it in a way that would make me feel comfortable sleep at night....
racial profiling is wrong, and bad. There should be a new stronger word, like bad wrong, or badong. Yes, profiling is badong. From this moment, u will stand for the opposite of profiling,
gnodab
.(##RESPBREAK##)16##DELIM##asakawa##DELIM##Hi Facesmasher,
You should notice from this post that any point you try to make gets completely ignored if you accompany the point with controversial and accusatory comments. The more emotionally charged a discussion is the more you need to try and detach from the emotive side of things and address the points raised.
I don't want to discourage you from taking part in discussions but I need you not to attack other forum-users.
Thanks.
Post by
MyTie
facesmasher - I'm not saying that racial profiling is right or moral. I'm saying it is statistically effective at fighting crime in some jurisdictions. I'm saying that fighting racial profiling by arguing it is statistically ineffective is
mathematically false
. I think if you or anyone wants to argue against racial profiling, do so because... well let me quote myself:Explain how this is wrong, or drop the arguments that racial profiling is ineffective, and do like the rest of the world and argue how it is unconstitutionally discriminatory, or immoral.Stuff like this:What are black people to you? Animals? Probably so.is completely uncalled for. I'm certainly not saying that racial profiling SHOULD be done, but that the correlation it has to reducing crime to levels not seen in 50 years shouldn't be ignored. I have my own reservations about stopping and frisking anyone, due to my feelings about searches and seizures. To say that because of that, I think that black people are "animals", is inflammatory and wrong.
I demand you retract the comment.
If not, I'll report you for this obvious and uncalled for attack.
Post by
168916
This post was from a user who has deleted their account.
Post by
Thror
What are black people to you? Animals? Probably so. That's what racial profiling is. Labeling and degrading people even before they commit the crime. That thought alone, is already racist.
And who are you to ask? What right do you have to stick your nose into MyTie's opinion of anyone? Did MyTie say he treats black people badly or something? Because I sure can not see that. He has the right to assume anything of anyone, and you have no right of judging his thoughts, until those thoughts become actions and he starts being mean to people. You are overreacting as hell here.
Post by
168916
This post was from a user who has deleted their account.
Post by
Squishalot
This is getting, a bit ridiculous.
Let me break it down for you and fenomas.
You made a comment saying that if '70% of crime is caused by blacks, then the black guy is more likely to be a criminal' or something along those lines, which fenomas disagreed with, on the basis of conditional probability (i.e. you can't look at headline numbers like that to derive the real underlying stats). You disagreed, and asked us to explain better. Here was the explanation.
Explain how this is wrong, or drop the arguments that racial profiling is ineffective, and do like the rest of the world and argue how it is unconstitutionally discriminatory, or immoral.
I'm assuming, therefore, that because I'm arguing with fenomas and not you, that you're not reading anything I'm saying in the other thread.
Post by
MyTie
This is getting, a bit ridiculous.
Let me break it down for you and fenomas.
You made a comment saying that if '70% of crime is caused by blacks, then the black guy is more likely to be a criminal' or something along those lines, which fenomas disagreed with, on the basis of conditional probability (i.e. you can't look at headline numbers like that to derive the real underlying stats). You disagreed, and asked us to explain better. Here was the explanation.I don't think you guys actually read what I was saying.
Post by
Squishalot
I don't think you guys actually read what I was saying.
I believe this is where I got the inference from:
The point of it all is that even if you knew that
90% of all crimes in a neighborhood were committed by blacks
, if you then went there and saw a white guy and a black guy and thought you knew which of them was more likely to be a criminal, you'd be incorrect.
No, I would be correct.
This is our point. How many crimes are caused by people is irrelevant, unless you factor in population size to work out the actual statistical probability. You can say all you like about agreeing that statistical probabilities should be used, but while you stand by the above statement, you're throwing it out the window and relying on the bias that fenomas is saying exists in the cops on the street.
Post by
MyTie
I don't think you guys actually read what I was saying.
I believe this is where I got the inference from:
The point of it all is that even if you knew that
90% of all crimes in a neighborhood were committed by blacks
, if you then went there and saw a white guy and a black guy and thought you knew which of them was more likely to be a criminal, you'd be incorrect.
No, I would be correct.
This is our point. How many crimes are caused by people is irrelevant, unless you factor in population size to work out the actual statistical probability. You can say all you like about agreeing that statistical probabilities should be used, but while you stand by the above statement, you're throwing it out the window and relying on the bias that fenomas is saying exists in the cops on the street.
Oh I see it now. My initial argument was re-framed, and I didn't read the strawman carefully enough. At this point, fenomas is addressing something that has nothing to do with my argument. In fact, it has nothing to do with racial profiling at all in the context it was being discussed. No wonder I was so confused. I'll have to pay closer attention when people switch gears on me. Wow. That is really irritating. It's irritating because, first and foremost, as I said, it has nothing to do with the conversation I was discussing, and second of all, it devolved the conversation to this stupid statistical argument. I can't even express how frustrating this is. To have such a great point, and then have it so effectively buried under an analysis of something completely different. I feel cheated out of the discussion I was in.
Post by
Squishalot
I'd say something about irony etc. etc., but let's leave it there.
Post by
168916
This post was from a user who has deleted their account.
Post by
MyTie
...wow. I feel like that principal in Happy Gilmore or whatever it was.
I will say this though - forget about me, I don't matter. Just please, please quit abusing the phrase "straw man". If it was one of your children it would be a ward of the state by now. Thank you, and may god have mercy on your soul.
Sorry. I don't usually use the term... maybe once a week, or a month or so. But with you it seems to come up a lot. You and HsR.
Post by
168916
This post was from a user who has deleted their account.
Post by
MyTie
My favorite:
only one side wants to limit the legal rights of others
Straw man. Neither side of this debate (currently) want that.
So, are you saying that gamerunknown was correct when he said that one side wants to limits the legal rights of others? Because that had never been my position. What do you call that fallacy when someone represents the arguments of someone else, but changes the argument to something else.... what is that called?
Post by
168916
This post was from a user who has deleted their account.
Post by
MyTie
So, are you saying that gamerunknown was correct when he said that one side wants to limits the legal rights of others? Because that had never been my position. What do you call that fallacy when someone represents the arguments of someone else, but changes the argument to something else.... what is that called?
That's not a fallacy, it's a disagreement. Fallacies are procedural errors - they are incorrect in form, regardless of whether the claim made is true or not. Asserting something incorrect (more precisely, something you think is incorrect) does not qualify as a fallacy,
even if the assertion involves a description of your position
.
There are two sides to this disagreement... the people that think there are strawman arguments (me), and the people that think that there is no such thing as a fallacy.
Post by
168916
This post was from a user who has deleted their account.
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