not able to understand a probability concept
$begingroup$
Suppose there are patients suffering from a particular lung disease.
Either lung is diseased with a probability of 0.1.
How to find the probability of exactly n lungs being diseased ?
n = { 0,1,2 }
If I think of binomial distribution then what will be the probability
of success, p ? Will it be 0.1 ? If yes,Why ?
probability binomial-distribution
$endgroup$
add a comment |
$begingroup$
Suppose there are patients suffering from a particular lung disease.
Either lung is diseased with a probability of 0.1.
How to find the probability of exactly n lungs being diseased ?
n = { 0,1,2 }
If I think of binomial distribution then what will be the probability
of success, p ? Will it be 0.1 ? If yes,Why ?
probability binomial-distribution
$endgroup$
add a comment |
$begingroup$
Suppose there are patients suffering from a particular lung disease.
Either lung is diseased with a probability of 0.1.
How to find the probability of exactly n lungs being diseased ?
n = { 0,1,2 }
If I think of binomial distribution then what will be the probability
of success, p ? Will it be 0.1 ? If yes,Why ?
probability binomial-distribution
$endgroup$
Suppose there are patients suffering from a particular lung disease.
Either lung is diseased with a probability of 0.1.
How to find the probability of exactly n lungs being diseased ?
n = { 0,1,2 }
If I think of binomial distribution then what will be the probability
of success, p ? Will it be 0.1 ? If yes,Why ?
probability binomial-distribution
probability binomial-distribution
asked Dec 6 '18 at 2:43
shikharshikhar
32
32
add a comment |
add a comment |
1 Answer
1
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oldest
votes
$begingroup$
"Either lung" means. Either the left lung, the right, lung or both.
So probability of either lung diseased is equal to $1 - P(text{neither lung diseased})$.
And the probability of neither lung is $P(text{left lung healthy})P(text{right lung healthy}) = P(text{a specific lung healthy})^2$.
And probability of $P(text{specific lung diseased}) = 1 -P(text{a specific lung healthy})$
So we have $P(text{either lung diseased}) = 1-P(text{a specific lung healthy})^2=.1$ so $ P(text{a specific lung healthy})= sqrt{.9}approx 0.949$
And $P(text{a specific lung diseased}) = 1 -sqrt{.9} approx 0.051$
====
The probability of $0$ lungs diseased is $1- P(text{either lung diseased}) = 1 - .1 = .9$.
Or we could say it is $P(text{specific lung healthy})^2 = sqrt{.9}^2 = .9$
The probability of $1$ lung diseased i $P(text{left lung diseased and right healty}) + P(text{right lung diseased and left healthy}) = 2P(text{specific lung diseased})P(text{specific lung healthy}) = 2sqrt{.9}(1 - sqrt{.9})approx 0.097$
The probability of $2$ lungs diseased is $P(text{specific lung diseased})^2 = (1 - sqrt{.9})^2 = 1 + .9 -2sqrt{.9} approx 0.003$
We can generalize as exactly $n$ lungs diseased as
$(text{# of ways to chose which lungs are diseased})P(text{specific n lungs are diseased})P(text{specific 2-n lungs are healthy})=$
${2 choose n}P(text {specific lung diseased})^nP(text{specific lung healthy})^{2-n}=$
${2 choose n} (1-sqrt{.9})^n sqrt{.9}^{2-n}$.
I have no idea what you mean by "probability of success". Success of what?
$endgroup$
$begingroup$
why is the probability of sucess equal to 0.1 ? Can you explain it more clearly please ?
$endgroup$
– shikhar
Dec 6 '18 at 14:50
1
$begingroup$
Um... because you said so. "Either lung is diseased with a probability of 0.1."
$endgroup$
– fleablood
Dec 6 '18 at 16:23
add a comment |
Your Answer
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1 Answer
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1 Answer
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active
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active
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active
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$begingroup$
"Either lung" means. Either the left lung, the right, lung or both.
So probability of either lung diseased is equal to $1 - P(text{neither lung diseased})$.
And the probability of neither lung is $P(text{left lung healthy})P(text{right lung healthy}) = P(text{a specific lung healthy})^2$.
And probability of $P(text{specific lung diseased}) = 1 -P(text{a specific lung healthy})$
So we have $P(text{either lung diseased}) = 1-P(text{a specific lung healthy})^2=.1$ so $ P(text{a specific lung healthy})= sqrt{.9}approx 0.949$
And $P(text{a specific lung diseased}) = 1 -sqrt{.9} approx 0.051$
====
The probability of $0$ lungs diseased is $1- P(text{either lung diseased}) = 1 - .1 = .9$.
Or we could say it is $P(text{specific lung healthy})^2 = sqrt{.9}^2 = .9$
The probability of $1$ lung diseased i $P(text{left lung diseased and right healty}) + P(text{right lung diseased and left healthy}) = 2P(text{specific lung diseased})P(text{specific lung healthy}) = 2sqrt{.9}(1 - sqrt{.9})approx 0.097$
The probability of $2$ lungs diseased is $P(text{specific lung diseased})^2 = (1 - sqrt{.9})^2 = 1 + .9 -2sqrt{.9} approx 0.003$
We can generalize as exactly $n$ lungs diseased as
$(text{# of ways to chose which lungs are diseased})P(text{specific n lungs are diseased})P(text{specific 2-n lungs are healthy})=$
${2 choose n}P(text {specific lung diseased})^nP(text{specific lung healthy})^{2-n}=$
${2 choose n} (1-sqrt{.9})^n sqrt{.9}^{2-n}$.
I have no idea what you mean by "probability of success". Success of what?
$endgroup$
$begingroup$
why is the probability of sucess equal to 0.1 ? Can you explain it more clearly please ?
$endgroup$
– shikhar
Dec 6 '18 at 14:50
1
$begingroup$
Um... because you said so. "Either lung is diseased with a probability of 0.1."
$endgroup$
– fleablood
Dec 6 '18 at 16:23
add a comment |
$begingroup$
"Either lung" means. Either the left lung, the right, lung or both.
So probability of either lung diseased is equal to $1 - P(text{neither lung diseased})$.
And the probability of neither lung is $P(text{left lung healthy})P(text{right lung healthy}) = P(text{a specific lung healthy})^2$.
And probability of $P(text{specific lung diseased}) = 1 -P(text{a specific lung healthy})$
So we have $P(text{either lung diseased}) = 1-P(text{a specific lung healthy})^2=.1$ so $ P(text{a specific lung healthy})= sqrt{.9}approx 0.949$
And $P(text{a specific lung diseased}) = 1 -sqrt{.9} approx 0.051$
====
The probability of $0$ lungs diseased is $1- P(text{either lung diseased}) = 1 - .1 = .9$.
Or we could say it is $P(text{specific lung healthy})^2 = sqrt{.9}^2 = .9$
The probability of $1$ lung diseased i $P(text{left lung diseased and right healty}) + P(text{right lung diseased and left healthy}) = 2P(text{specific lung diseased})P(text{specific lung healthy}) = 2sqrt{.9}(1 - sqrt{.9})approx 0.097$
The probability of $2$ lungs diseased is $P(text{specific lung diseased})^2 = (1 - sqrt{.9})^2 = 1 + .9 -2sqrt{.9} approx 0.003$
We can generalize as exactly $n$ lungs diseased as
$(text{# of ways to chose which lungs are diseased})P(text{specific n lungs are diseased})P(text{specific 2-n lungs are healthy})=$
${2 choose n}P(text {specific lung diseased})^nP(text{specific lung healthy})^{2-n}=$
${2 choose n} (1-sqrt{.9})^n sqrt{.9}^{2-n}$.
I have no idea what you mean by "probability of success". Success of what?
$endgroup$
$begingroup$
why is the probability of sucess equal to 0.1 ? Can you explain it more clearly please ?
$endgroup$
– shikhar
Dec 6 '18 at 14:50
1
$begingroup$
Um... because you said so. "Either lung is diseased with a probability of 0.1."
$endgroup$
– fleablood
Dec 6 '18 at 16:23
add a comment |
$begingroup$
"Either lung" means. Either the left lung, the right, lung or both.
So probability of either lung diseased is equal to $1 - P(text{neither lung diseased})$.
And the probability of neither lung is $P(text{left lung healthy})P(text{right lung healthy}) = P(text{a specific lung healthy})^2$.
And probability of $P(text{specific lung diseased}) = 1 -P(text{a specific lung healthy})$
So we have $P(text{either lung diseased}) = 1-P(text{a specific lung healthy})^2=.1$ so $ P(text{a specific lung healthy})= sqrt{.9}approx 0.949$
And $P(text{a specific lung diseased}) = 1 -sqrt{.9} approx 0.051$
====
The probability of $0$ lungs diseased is $1- P(text{either lung diseased}) = 1 - .1 = .9$.
Or we could say it is $P(text{specific lung healthy})^2 = sqrt{.9}^2 = .9$
The probability of $1$ lung diseased i $P(text{left lung diseased and right healty}) + P(text{right lung diseased and left healthy}) = 2P(text{specific lung diseased})P(text{specific lung healthy}) = 2sqrt{.9}(1 - sqrt{.9})approx 0.097$
The probability of $2$ lungs diseased is $P(text{specific lung diseased})^2 = (1 - sqrt{.9})^2 = 1 + .9 -2sqrt{.9} approx 0.003$
We can generalize as exactly $n$ lungs diseased as
$(text{# of ways to chose which lungs are diseased})P(text{specific n lungs are diseased})P(text{specific 2-n lungs are healthy})=$
${2 choose n}P(text {specific lung diseased})^nP(text{specific lung healthy})^{2-n}=$
${2 choose n} (1-sqrt{.9})^n sqrt{.9}^{2-n}$.
I have no idea what you mean by "probability of success". Success of what?
$endgroup$
"Either lung" means. Either the left lung, the right, lung or both.
So probability of either lung diseased is equal to $1 - P(text{neither lung diseased})$.
And the probability of neither lung is $P(text{left lung healthy})P(text{right lung healthy}) = P(text{a specific lung healthy})^2$.
And probability of $P(text{specific lung diseased}) = 1 -P(text{a specific lung healthy})$
So we have $P(text{either lung diseased}) = 1-P(text{a specific lung healthy})^2=.1$ so $ P(text{a specific lung healthy})= sqrt{.9}approx 0.949$
And $P(text{a specific lung diseased}) = 1 -sqrt{.9} approx 0.051$
====
The probability of $0$ lungs diseased is $1- P(text{either lung diseased}) = 1 - .1 = .9$.
Or we could say it is $P(text{specific lung healthy})^2 = sqrt{.9}^2 = .9$
The probability of $1$ lung diseased i $P(text{left lung diseased and right healty}) + P(text{right lung diseased and left healthy}) = 2P(text{specific lung diseased})P(text{specific lung healthy}) = 2sqrt{.9}(1 - sqrt{.9})approx 0.097$
The probability of $2$ lungs diseased is $P(text{specific lung diseased})^2 = (1 - sqrt{.9})^2 = 1 + .9 -2sqrt{.9} approx 0.003$
We can generalize as exactly $n$ lungs diseased as
$(text{# of ways to chose which lungs are diseased})P(text{specific n lungs are diseased})P(text{specific 2-n lungs are healthy})=$
${2 choose n}P(text {specific lung diseased})^nP(text{specific lung healthy})^{2-n}=$
${2 choose n} (1-sqrt{.9})^n sqrt{.9}^{2-n}$.
I have no idea what you mean by "probability of success". Success of what?
edited Dec 6 '18 at 16:49
answered Dec 6 '18 at 6:11
fleabloodfleablood
69.7k22685
69.7k22685
$begingroup$
why is the probability of sucess equal to 0.1 ? Can you explain it more clearly please ?
$endgroup$
– shikhar
Dec 6 '18 at 14:50
1
$begingroup$
Um... because you said so. "Either lung is diseased with a probability of 0.1."
$endgroup$
– fleablood
Dec 6 '18 at 16:23
add a comment |
$begingroup$
why is the probability of sucess equal to 0.1 ? Can you explain it more clearly please ?
$endgroup$
– shikhar
Dec 6 '18 at 14:50
1
$begingroup$
Um... because you said so. "Either lung is diseased with a probability of 0.1."
$endgroup$
– fleablood
Dec 6 '18 at 16:23
$begingroup$
why is the probability of sucess equal to 0.1 ? Can you explain it more clearly please ?
$endgroup$
– shikhar
Dec 6 '18 at 14:50
$begingroup$
why is the probability of sucess equal to 0.1 ? Can you explain it more clearly please ?
$endgroup$
– shikhar
Dec 6 '18 at 14:50
1
1
$begingroup$
Um... because you said so. "Either lung is diseased with a probability of 0.1."
$endgroup$
– fleablood
Dec 6 '18 at 16:23
$begingroup$
Um... because you said so. "Either lung is diseased with a probability of 0.1."
$endgroup$
– fleablood
Dec 6 '18 at 16:23
add a comment |
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