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Quick S1 Question

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I just don't understand the part I put a box around in the second picture
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Zacken
22
Original post by creativebuzz
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I just don't understand the part I put a box around in the second picture


Let's call it them (married couple 1) = MC1 and (married couple 2) = MC2

Then, in any two couples - you want P(only 1 husband and only 1 wife).

Which is P(MC1 both has degree)P(MC2 neither has degree) + P(MC2 both has degree + MC1 both has degree) + (stuff)

= 1124×43120+1124×43120=2(1124×43120)\frac{11}{24} \times \frac{43}{120} + \frac{11}{24} \times \frac{43}{120} = 2\left(\frac{11}{24} \times \frac{43}{120}\right)

The +(stuff) is the bit you already understand, I think.
Original post by creativebuzz
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I just don't understand the part I put a box around in the second picture


Box part refers to the last two semicolon delimited items in the previous line.

If only one husband and one wife have a degree, then either.

a) the two with degrees are in defferent couples - the first two items in the pervious line, or

b) they are in the same couple. I.e. husband and wife of one couple both have degrees, and in the other couple neither has a degree.

Edit: I've been ninga'd. :eek:
(edited 7 years ago)
Reply 3
Avatar for Zacken
Zacken
22
Original post by ghostwalker


Edit: I've been ninga'd. :eek:


Nobody replies for an hour and then we both reply within the span of a minute. :lol:
Original post by ghostwalker
Box part refers to the last two semicolon delimited items in the previous line.

If only one husband and one wife have a degree, then either.

a) the two with degrees are in defferent couples - the first two items in the pervious line, or

b) they are in the same couple. I.e. husband and wife of one couple both have degrees, and in the other couple neither has a degree.

Edit: I've been ninga'd. :eek:


But for the first part multiplication they did

2xp(only husband)xp(only wife) but don't they have to multiply that by P(not the other husband having it)x(not the other wife having it) to complete the sample set of (Husband A having a degree, Wife A having a degree, Husband B not having a degree, Wife B not having a degree)
Original post by Zacken
Let's call it them (married couple 1) = MC1 and (married couple 2) = MC2

Then, in any two couples - you want P(only 1 husband and only 1 wife).

Which is P(MC1 both has degree)P(MC2 neither has degree) + P(MC2 both has degree + MC1 both has degree) + (stuff)

= 1124×43120+1124×43120=2(1124×43120)\frac{11}{24} \times \frac{43}{120} + \frac{11}{24} \times \frac{43}{120} = 2\left(\frac{11}{24} \times \frac{43}{120}\right)

The +(stuff) is the bit you already understand, I think.


Oh I understand the second multiplication now, thanks! Would you mind giving me a hand on this question?

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I have no idea where I went wrong and what the hell they're doing :P

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Original post by Zacken
Nobody replies for an hour and then we both reply within the span of a minute. :lol:


Hey Zacken, hate to be a pain but could you give me a hand on the regression question I posted!
Reply 7
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Zacken
22
I'm about to go offline right now, so hopefully someone else will help you!
Original post by creativebuzz
Oh I understand the second multiplication now, thanks! Would you mind giving me a hand on this question?

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I have no idea where I went wrong and what the hell they're doing :P

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Check your formula book or textbook. The first thing I notice is that you've confused ∑xy\sum xy with SxyS_{xy} or sxys_{xy}.

Not checked beyond that.
Original post by ghostwalker
Check your formula book or textbook. The first thing I notice is that you've confused ∑xy\sum xy with SxyS_{xy} or sxys_{xy}.

Not checked beyond that.


No need to check anything else! That's where I went wrong (so stupid)! But thank you, I've got the answer right now :smile:

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