Mixing
Quick question on multiplication of summations
$begingroup$
Suppose I have this situation
$$sum_{i=1}^n X_i f(X_i) times sum_{i=1}^n X_i^2 f(X_i)$$
There's no way this could be $sum_{i=1}^n X_i^3f(X_i)$, right? I'm working on a proof involving expected value and if this is true the proof finishes nicely. If it isn't, I have no clue at all where to go, yet this doesn't seem logical to me.
summation expected-value
asked Jan 30 at 3:14
JohnJohn
517
$endgroup$
add a comment |
$begingroup$
Suppose I have this situation
$$sum_{i=1}^n X_i f(X_i) times sum_{i=1}^n X_i^2 f(X_i)$$
There's no way this could be $sum_{i=1}^n X_i^3f(X_i)$, right? I'm working on a proof involving expected value and if this is true the proof finishes nicely. If it isn't, I have no clue at all where to go, yet this doesn't seem logical to me.
summation expected-value
asked Jan 30 at 3:14
JohnJohn
517
$endgroup$
add a comment |
$begingroup$
Suppose I have this situation
$$sum_{i=1}^n X_i f(X_i) times sum_{i=1}^n X_i^2 f(X_i)$$
There's no way this could be $sum_{i=1}^n X_i^3f(X_i)$, right? I'm working on a proof involving expected value and if this is true the proof finishes nicely. If it isn't, I have no clue at all where to go, yet this doesn't seem logical to me.
summation expected-value
asked Jan 30 at 3:14
JohnJohn
517
$endgroup$
Suppose I have this situation
$$sum_{i=1}^n X_i f(X_i) times sum_{i=1}^n X_i^2 f(X_i)$$
There's no way this could be $sum_{i=1}^n X_i^3f(X_i)$, right? I'm working on a proof involving expected value and if this is true the proof finishes nicely. If it isn't, I have no clue at all where to go, yet this doesn't seem logical to me.
summation expected-value
summation expected-value
asked Jan 30 at 3:14
JohnJohn
517
asked Jan 30 at 3:14
JohnJohn
517
asked Jan 30 at 3:14
JohnJohn
517
asked Jan 30 at 3:14
JohnJohn
517
asked Jan 30 at 3:14
JohnJohn
517
517
add a comment |
add a comment |
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