ECMT Quiz 3 (1 Viewer)

[Some_Guy]

Anyone know how to do ANY of part 3?
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[what971]

Nope.

And I got Acct test on the same day too, oh my I am ****ed.

 

[adambra]

Anyone know how to do ANY of part 3?
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Can't do any of any part...

 

[what971]

Some Guy, I've actually looked through it and am confident about 2 and 3, I have no idea about 1 though... Will (hopefully) post answers later after Acct assessment hand in. That is, after Wednesday.

 

[Some_Guy]

Im pretty sure chp 8 of the book covers part 1.

part 3 i think is the excel stuff which i wasnt paying attention for
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[what971]

oh k! thanks! I was just looking at chpt 12, thats why. Will work through after Acct.

 

[Some_Guy]

so can anyone help with the part 3 stuff?
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[Some_Guy]

.
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[Some_Guy]

argh i just went over part two and theres stuff i dont get there.

particuarly the covariance stuff. the word covariance makes no appearance in the book and no intelligible appearance in the notes.
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[jpr333]

It should do...
http://mathworld.wolfram.com/images/equations/Covariance/equation1.gif

 

[what971]

Yeah I did the first part alright, I've been working through the second part and then I got sleepy... so ended up here on BoS again. :/

 

[what971]

Come on guys.... let's discuss... (ie. share answers)...

I'll give you the answers for Q1 if you give me the answers for Q2......

 

[what971]

haha...Noone's going to blame you for that lol. I cbf as well, but unfortunately I HAVE to do it.....

 

[what971]

k. I rang two of my friends I made in the tutes, one hasn't started (wtf) while the other's still stuck in part 2 and we both came to the conclusion that the part 2 question was er... impossible to do. Did anyone here also come to the same conclusion?

PS Is anyone here at all?

Also, Lecture Notes/Textbook does not seem to help at all. ECMT = the worstest subject in the history.

 

[Some_Guy]

I think the numbers in part 2 a) are wrong and that theres no way to get the right answer with them.
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[adambra]

zomg now u tell, spent a whole 3minutes on it. now i only have 12 left...

 

[what971]

I think 2a) and 2b) are both wrong, c, d, e seem fine however.

The problem for me is finding the correlation and co-efficient between X and Y, I can do it but it takes me ages and I can't help feeling there must be a shorter way. ???

@Brogan. It's true. Also it's from New Zealand. We Lose.

 

[what971]

zomg now u tell, spent a whole 3minutes on it. now i only have 12 left...

...12... what left?

 

[what971]

oh guys, someone tell me what 'marginal distribtion' is, please??

 

[cimbom]

Yeah so for like 2, d. the marginal distribution of X would be

Pr(X=1)= 0.04 + 0.07 = 0.11
Pr(X=2) = 0.14 + 0.17 = 0.31
Pr(X=3) = 0.23 + 0.23 = 0.46
Pr(X=4) = 0.07 + 0.05 = 0.12

and i don't think there's any simpler way to calculate the coefficient of correlation- we have to get E(X), E(Y), Var(X) and Var(Y) with the super- long sum formulas... that we learnt at the beginning of the semester, with the table.

E(X) = sum (Pr(X=xi) . xi)
Var(X) = sum (xi- E(X))^2 . Pr(X=xi)

... and then do the same thing for Y...
and then you use the joint probability table, with the next formula, it takes ages .

what971- get the mark berenson text book from last year to understand part3. it explains anova tables and everything. ch13... it should be in special reserve; if not on undergraduate shelf (i couldn't find it) 'basic business statistics'.