Skip to main content
P
ptc-58202801-Visitor
1-Visitor
May 18, 2014
Solved

Summation for empirical dispersion

  • May 18, 2014
  • 1 reply
  • 1743 views

Hi. How do I write and describe this summation:

das.jpg

in Mathad Prime 3.0?

P.S. Dont mind the second X in brackets, I can't find a way to describe Xi.

Best answer by Werner_E

Here you are. As already written you have to use the vector index you get either from the ribbon menu or by typing [

In case you don't know - Mathcad has a lot of built-in statistical functions, standard deviation (you are calculating the square of it) is one of them, so you may use it. See attached sheet.

1 reply

W
Werner_E25-Diamond I
25-Diamond I
May 18, 2014

X should be a data vector consisting of n elements. You have to use the matrix/vector index for Xi (writing X[i), not the literal index you get with Ctrl&-.

You might also consider to sum from 0 to n-1 rather than from 1 to n or change the system variable ORIGIN to 1.

If this doesn't help come back and privide a Mathcad sheet to work on.

P
ptc-58202801-VisitorAuthor
1-Visitor
May 18, 2014

I'm really not sure how does data vector work. I've attached what I've came up so far. Could you solve this for me?

W
Werner_E25-Diamond IAnswer
25-Diamond I
May 18, 2014

Here you are. As already written you have to use the vector index you get either from the ribbon menu or by typing [

In case you don't know - Mathcad has a lot of built-in statistical functions, standard deviation (you are calculating the square of it) is one of them, so you may use it. See attached sheet.

    Terms & ConditionsAccessibility statement