Homework Statement
Suppose there are two urns that contain white and yellow balls. Urn 1 contains
10 white and 5 yellow balls, and Urn 2 contains 6 white and 12 yellow balls. You
are going to draw 3 balls without replacement from one of the urns. To decide
which urn to draw from, you will...
Thanks for the reassurance, I appreciate it. I don't have much experience in the math stats setting as I recently switched into the Statistics major, but I think I'm getting the hang of it.
Homework Statement
The NHL currently has a total of 30 teams in 4 divisions (7 teams in the Pacific
Division, 7 in the Central Division, 8 in the Metropolitan Division, and 8 in the
Atlantic Division). Suppose the NHL gets a new commissioner, and they have
the curious notion of...
Sorry, I'm very slow at typing this latex code..
\overline{y}*[\sum(\overline{x} - x_{i})] = 0
[\sum(\overline{x} - x_{i})] = 0
\sum(\overline{x}) - \sum(x_{i}) = 0
n(\overline{x}) - n(\overline{x}) = 0
LHS = RHS
used
\sum(c) = n*c
Where n is the upper bound and 1 is the lower...
I'm a little bit rusty on my operation of sums, so excuse me if this is incorrect, but can I do this?
[(\overline{y})/n][\sum x_{i}] - \overline{y}[\sum x_{i}]
= [(\overline{y}^2)/n][\sum(x_{i} - x_{i})]
Then what tends to zero appears to be obvious
I've figured out why, but I'm not sure how to explain it symbolically, do you think I would need to elaborate more or is my edited explanation good enough in your view?
Thanks for the help!
Ok, so I actually did end up getting somewhere and didn't realize it =)
EDIT:
I've done proof
\sum[(x_{i}-\overline{x})y_{i}] + \sum[\overline{y}(\overline{x} - x_{i})]
Playing around in excel has taught me that \sum[\overline{y}(\overline{x} - x_{i})] is actually just equal to...
Homework Statement
Prove that
\sum[(x_{i} - \overline{x})(y_{i} - \overline{y})] = \sum[(x_{i} - \overline{x})y_{i}]
Homework Equations
None.
The Attempt at a Solution
I tried using the fact that the sum of the mean values is just the mean value, because the sum of a constant...
Thanks for all the replies, I'm actually not planning on pursuing anything past a Master's degree in statistics, I'd like to get into the industry as soon as possible.
I'll definitely look into expanding my knowledge of linear algebra, as I know it's used quite a lot in statistics. I'll also...
Yeah, I'm just finishing a mathematical statistics course right now (the first of two) and it is somewhat centered around proofs. That being said, I found it to be an alright class to take.
I'll probably go ahead and take more linear algebra instead of vector calculus, as I have room for it.
I've taken a multi-variable calculus course already that covers infinite sequences and series, Taylor's theorem, quadratics surfaces, double and triple integration etc.
I'm looking to get a Master's Degree in statistics two years from now, is there any point of me taking a class that involves...
I'm having a little bit of trouble understanding the equation of a cone..
It is given by (x^2)/(a^2) + (y^2)/(b^2) = (z^2)/(c^2)
I understand that if a ≠ b you have an elliptical cone, but I'm not sure how to set the equation up to define the cone as having a height.
Can anyone clarify...