Further Statistics Edexcel 9FM/3B 16th June

@Evil Homer Hi could you please add this group?

Reply 3

Heisenberg66

OP

Original post by DianaG04

Good point, how are you feeling about it? Any particular hard questions you’ve come across?

I feel like 2021 and 2022 papers have been the most difficult ones yet. Not feeling too great about this one but I guess we will have to see tomorrow

Reply 4

ReneeS22

does any one have a good way of recognising which distribution is the correct one to use? I always get confused in the hypothesis type questions

Reply 5

Heisenberg66

OP

Original post by ReneeS22

does any one have a good way of recognising which distribution is the correct one to use? I always get confused in the hypothesis type questions

Unfortunately there isn't really another way except of learning the definitions of them and assessing the context using the definitions.

Reply 6

Original post by ReneeS22

does any one have a good way of recognising which distribution is the correct one to use? I always get confused in the hypothesis type questions

The Poisson distribution is the easiest to recognise as they will tell you the mean rate of something happening.

The geometric distribution I always used to mix up with the negative binomial distribution. This is because both have a constant value of the probability parameter p. However, the negative binomial distribution is used to find the number of trials needed to achieve a fixed number of successes, as opposed to the minimum number of trials needed for a single success (for which, ofc the geometric distribution is required).

Reply 7

ReneeS22

Original post by TypicalNerd

The Poisson distribution is the easiest to recognise as they will tell you the mean rate of something happening.

The geometric distribution I always used to mix up with the negative binomial distribution. This is because both have a constant value of the probability parameter p. However, the negative binomial distribution is used to find the number of trials needed to achieve a fixed number of successes, as opposed to the minimum number of trials needed for a single success (for which, ofc the geometric distribution is required).

The geometric and binomial are the ones I mix up the most! thanks so much that makes sense.

Reply 8

Original post by ReneeS22

The geometric and binomial are the ones I mix up the most! thanks so much that makes sense.

Well, I suppose my description of the geometric distribution was a little incomplete.

The geometric distribution is used find the probability that the first success occurs on the nth trial. As such, if we define x as the probability of success and n as the number of successive trials:

P(first success occurs on trial n) = x(1 - x)^(n-1)

Reply 9

That felt a hell of a lot easier than CP1, CP2 and FM1.

Considering FP1 is my best paper, if FS1 has gone well for me, that potentially bodes well for me and perhaps I can salvage the blunderfest that has been further maths so far.

(edited 10 months ago)

Reply 10

Clocky265

Does anyone remember what answers they got?

Reply 11

Jamie5040

Did u answer all of the questions

Reply 12

Faisal Amiri

6

Last question probability of Red on 4th was greater.

Reply 13

Original post by Faisal Amiri

Last question probability of Red on 4th was greater.

It was ever so slightly iirc. 0.5904 vs 0.5801 or something.

Reply 14

Original post by Jamie5040

Did u answer all of the questions

Almost. I stupidly forgot how to calculate probabilities of type 2 errors, so I lost marks there.

Reply 15

csio

Original post by TypicalNerd

It was ever so slightly iirc. 0.5904 vs 0.5801 or something.

i got that too

Reply 16

Clocky265

Original post by Faisal Amiri

Last question probability of Red on 4th was greater.

Got that as well

Reply 17

BambooEnjoyer

How many marks would I lose for the Poisson question about the 900 calls worth 4 marks where gamma = 3 if I only figured out gamma? It was a nasty question in terms of understanding where the time spent on it wouldn't be worth the marks I reckon so I finished the rest and had 5 mins at the end to have another go at it.

(edited 10 months ago)

Reply 18