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Reply 1
I had it :smile:

It better have been bloody Spearman's Rank! It started off with that, and was then followed by calculating a regression line for the data.

Was the result significant for the very last question??
Reply 2
AAA POOP. Can't believe I can't read :frown: 10 marks down the pooer. And i put that it wasn't significant. Im sad :frown:
Reply 3
That must be really annoying :frown:

I'm sure you'll get some method marks maybe, and also the hypothesis test you should manage to get a good chunk of those marks if you did it correctly as it is all method.
Reply 4
Nah I won't get method marks for either question, I've seen previous mark schemes! But cheers anyway :smile:.... Bring on first A-level re-take... :smile:
Reply 5
greenjm90
I had it :smile:

It better have been bloody Spearman's Rank! It started off with that, and was then followed by calculating a regression line for the data.

Was the result significant for the very last question??


Nope it wasn't, was nice they stated the hypothesis and definition of u for us:smile: . Enjoyed the paper and only got a bit stupidly mixed up with a few questions. The problem is with S2 for me though is the calculations, very simple I know but with quite a few to do on things like chi squared I often get a bit careless and will just forget to square O-E on 1 of them or something which of course could lose me several marks, so just hope I checked everything through properly.
Reply 6
I had it. I couldn't get the variance :zomg: Totally forgot the formula :mad:

Did you get "not significant" for both of the last parts?
Reply 7
For the clover question...

just after working out the mean and the variance, it asked you to relate your answers to (v) and (vi) to the suitability of a poisson distrubution. What did people say about how the expected number of samples to contain a four leaf clover (7.87?? anyone else get that??) related to the fit of a poisson?
Reply 8
jayshah31
I had it. I couldn't get the variance :zomg: Totally forgot the formula :mad:

Did you get "not significant" for both of the last parts?


Yep neither of them were significant :smile:

I think I got 0.47 for the variance? Anyone else get the same?!?!
Reply 9
Yes I got 0.47, but that was only after I saw that the mean had to be close to the variance (I think!) meaning I needed to divide by n-1.

The variance formula I used was sum of fx^2-sum of n*mean^2/n-1.

I got not significant for the last 2 questions as well.
What did every get for A and B, and the mean and standard deviation for the question where we had to calc it.

Er
mean = 116/156-157/166 - memory is awful
Deviation ~ 25
A ~ 217
B ~ 116

Any bells?
jayshah31
What did every get for A and B, and the mean and standard deviation for the question where we had to calc it.

Er
mean = 116/156-157/166 - memory is awful
Deviation ~ 25
A ~ 217
B ~ 116

Any bells?


I got 166.6 for the mean and 25.63 for the standard deviation. I got something like 120 for a and 220 for b, but I'm not entirely sure that they're even remotely right. That question threw me slightly.

What did people get for the three hypothesis tests we had to do? For the first one (it was in question 1, I think) I rejected H0 and for the two in question four I accepted H0 for both of them.
Reply 12
:| i got significant for the last two. for the chi test i got 11.18.
icysquall
I got 166.6 for the mean and 25.63 for the standard deviation. I got something like 120 for a and 220 for b, but I'm not entirely sure that they're even remotely right. That question threw me slightly.

What did people get for the three hypothesis tests we had to do? For the first one (it was in question 1, I think) I rejected H0 and for the two in question four I accepted H0 for both of them.

Yes! That's the mean and deviation.

I think there was an large range a and b can take, implied by the way the question was worded. I took P(Y < a) = 2.5%, then P(Y < b) to be 97.5%. Therefore, P(a < Y < b) = 95. From there, I proceeded to get the values of a and b. I then did P(Y < b) - P(Y < a) and got 0.95.
icysquall
I got 166.6 for the mean and 25.63 for the standard deviation. I got something like 120 for a and 220 for b, but I'm not entirely sure that they're even remotely right. That question threw me slightly.

What did people get for the three hypothesis tests we had to do? For the first one (it was in question 1, I think) I rejected H0 and for the two in question four I accepted H0 for both of them.


Yeh i got the same mean and standard deviation as you, but i can't remember what i got for a and b. I also the all the same hypothesis reults as you too.
Reply 15
jayshah31
What did every get for A and B, and the mean and standard deviation for the question where we had to calc it.

Er
mean = 116/156-157/166 - memory is awful
Deviation ~ 25
A ~ 217
B ~ 116

Any bells?


I've got the same. But I'm not sure if it's right :frown:
why people got the same cocnlusion for question 4???? :s-smilie: I can't remember but I rejected H0 in one part and accepted H0 in the other part. So I could've lost like 5 marks :frown:
Reply 16
icysquall
I got 166.6 for the mean and 25.63 for the standard deviation.


That sounds right.

icysquall
I got something like 120 for a and 220 for b, but I'm not entirely sure that they're even remotely right. That question threw me slightly.


The easiest way was to pick two suitable standardized values and work out what the original values would have been.

What did people get for the three hypothesis tests we had to do? For the first one (it was in question 1, I think) I rejected H0 and for the two in question four I accepted H0 for both of them.


Same; same as the rest of my FM class.
julija
I've got the same. But I'm not sure if it's right :frown:
why people got the same cocnlusion for question 4???? :s-smilie: I can't remember but I rejected H0 in one part and accepted H0 in the other part. So I could've lost like 5 marks :frown:

It just happened to be that way ... both critical values were greater than what they were tested against. Thus, H0 was accepted twice.
On the spearman's rank question was it a one tailed or a two tailed test?
It really confused me but both of them gave the same conclusion, so that was good!
Revive_Urself
On the spearman's rank question was it a one tailed or a two tailed test?
It really confused me but both of them gave the same conclution, so that was good!

Two tailed, I think.