Been struggling to fill in the blanks... can anyone help?
"If $X$ is an exponential random variable with a mean of $m$, then $\text{Var}(X)=m^2$"-question
1
$\begingroup$
probability-distributions
exponentiation
-
2Hint: I wonder if the _square root_ of the variance is a parameter of any importance in probability or statistics? – 2012-03-07
-
0Is the square root of the variance the same as the standard deviation? – 2012-03-07
-
1Yes, the positive square root of the variance is called the standard deviation. What is the value of the _standard deviation_ of an exponential random variable with _mean_ $m$? If you still have difficulty finishing the problem you are working on (homework?), [say not the struggle not availeth.](http://homepages.wmich.edu/~cooneys/poems/Clough.struggle.html) – 2012-03-07
-
0I'm thinking that it would be the root mean or am I getting the wrong gist of things? – 2012-03-07
-
1I give up. There are two blanks that you are struggling to fill in. One of them (doesn't matter whether it is the first or the second blank) should be filled in with the only four-letter word that occurs **twice** in the question that you posed above, while the other blank should be filled in with a two-word phrase (consisting of a eight-letter adjective qualifying a nine-letter noun) that has been used **twice** in the four comments above. – 2012-03-07
-
0Mean and standard deviation? – 2012-03-08
-
0Yes. I am glad you finally got there. – 2012-03-08