What does E(X-Y) represent in a joint pdf
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The situation is that X and Y are proportions of correct answers on science and humanities exams respectively. Their joint pdf is
f(x,y) = .4(2x+3y) for X & Y = [0,1]
My homework asks for E(Y-X), which was easy enough, but what I don't understand is how would I interpret expected values like this? Would E(Y-X) simply be: the average proportion of correct answers on humanities minus average proportion of correct answer on science
And would such a simple explanation also be used to explain the significance of scenarios such as E(XY)?
probability expected-value
asked Dec 5 '18 at 0:53
ajdawgajdawg
32
$endgroup$
add a comment |
$begingroup$
The situation is that X and Y are proportions of correct answers on science and humanities exams respectively. Their joint pdf is
f(x,y) = .4(2x+3y) for X & Y = [0,1]
My homework asks for E(Y-X), which was easy enough, but what I don't understand is how would I interpret expected values like this? Would E(Y-X) simply be: the average proportion of correct answers on humanities minus average proportion of correct answer on science
And would such a simple explanation also be used to explain the significance of scenarios such as E(XY)?
probability expected-value
asked Dec 5 '18 at 0:53
ajdawgajdawg
32
$endgroup$
add a comment |
$begingroup$
The situation is that X and Y are proportions of correct answers on science and humanities exams respectively. Their joint pdf is
f(x,y) = .4(2x+3y) for X & Y = [0,1]
My homework asks for E(Y-X), which was easy enough, but what I don't understand is how would I interpret expected values like this? Would E(Y-X) simply be: the average proportion of correct answers on humanities minus average proportion of correct answer on science
And would such a simple explanation also be used to explain the significance of scenarios such as E(XY)?
probability expected-value
asked Dec 5 '18 at 0:53
ajdawgajdawg
32
$endgroup$
The situation is that X and Y are proportions of correct answers on science and humanities exams respectively. Their joint pdf is
f(x,y) = .4(2x+3y) for X & Y = [0,1]
My homework asks for E(Y-X), which was easy enough, but what I don't understand is how would I interpret expected values like this? Would E(Y-X) simply be: the average proportion of correct answers on humanities minus average proportion of correct answer on science
And would such a simple explanation also be used to explain the significance of scenarios such as E(XY)?
probability expected-value
probability expected-value
asked Dec 5 '18 at 0:53
ajdawgajdawg
32
asked Dec 5 '18 at 0:53
ajdawgajdawg
32
asked Dec 5 '18 at 0:53
ajdawgajdawg
32
asked Dec 5 '18 at 0:53
ajdawgajdawg
32
asked Dec 5 '18 at 0:53
ajdawgajdawg
32
32
add a comment |
add a comment |
1 Answer
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The interpretation is: the average of the difference between the proportion of correct answers in science and the proportion of correct answers in humanities
In general if $g = g(X, Y)$ then $mathbb{E}[g(X,Y)]$ means the average of $g(X, Y)$
answered Dec 5 '18 at 1:03
caveraccaverac
14.5k31130
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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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$begingroup$
The interpretation is: the average of the difference between the proportion of correct answers in science and the proportion of correct answers in humanities
In general if $g = g(X, Y)$ then $mathbb{E}[g(X,Y)]$ means the average of $g(X, Y)$
answered Dec 5 '18 at 1:03
caveraccaverac
14.5k31130
$endgroup$
add a comment |
$begingroup$
The interpretation is: the average of the difference between the proportion of correct answers in science and the proportion of correct answers in humanities
In general if $g = g(X, Y)$ then $mathbb{E}[g(X,Y)]$ means the average of $g(X, Y)$
answered Dec 5 '18 at 1:03
caveraccaverac
14.5k31130
$endgroup$
add a comment |
$begingroup$
The interpretation is: the average of the difference between the proportion of correct answers in science and the proportion of correct answers in humanities
In general if $g = g(X, Y)$ then $mathbb{E}[g(X,Y)]$ means the average of $g(X, Y)$
answered Dec 5 '18 at 1:03
caveraccaverac
14.5k31130
$endgroup$
The interpretation is: the average of the difference between the proportion of correct answers in science and the proportion of correct answers in humanities
In general if $g = g(X, Y)$ then $mathbb{E}[g(X,Y)]$ means the average of $g(X, Y)$
answered Dec 5 '18 at 1:03
caveraccaverac
14.5k31130
answered Dec 5 '18 at 1:03
caveraccaverac
14.5k31130
answered Dec 5 '18 at 1:03
caveraccaverac
14.5k31130
answered Dec 5 '18 at 1:03
caveraccaverac
14.5k31130
14.5k31130
add a comment |
add a comment |
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