Arsey's S1 Edexcel Answers 18th Jan 2013

got exactly the same

Congratulationa!

91 - A

Got 86 - but seriously, I have no idea how I got that mark... Did like one or two past papers and I was just playing with numbers for that whole exam.. It felt like I didn't even have a clue what I was doing..

My son got 96% but was angry with the poor English/ ambigious meaning of some of the questions. It could have cost him more than it did...

Hi, just got a photocopy of my paper back, I got 90 UMS overall (68) but I'm hoping to get higher and looking at the paper for question 4c I got 0 marks but...

I got everything up to p(L>133)=0.0139
and I got 0 marks? Surely that is at least 2 method marks

[This is using Arsey's markscheme]

I didn't get the part about dividing 133 by 127.

Should I get this remarked? I want to get at least 94 UMS, otherwise I will have to retake the paper (since I need to get higher marks in the easy modules so that I can afford mistakes in further maths papers).


Apart from that can someone assess the Katie question answer that I wrote? I only got 1 mark out of 2, may be viable for the full two marks... (thank you for all your help!)
"I would not use normal distribution to model weekly income since the data is positively skewed with a coefficient of 0.757 whilst a normal distribution is symmetrical, i.e. it has no skew.
Also the probability of 240<=y<=400 = 0.52
0.52 calculated via (frequency from 240-400 / Sum of f)
which is quite far from her value of 0.404, showing her model is unreliable.
Therefore Katie's suggestion is bad and wrong. Even here [sic] mean (320) and standard deviation (150) are not the true values of the data which are 316 and 157 respectively, however they are close"

On the official mark scheme you have to use the conditional part of the question to get the marks, which is annoying! How much did it cost to get your script back?


Posted from TSR Mobile

£10

Please can you link me the official mark scheme?

can someone assess the Katie question answer that I wrote? I only got 1 mark out of 2, may be viable for the full two marks... (thank you for all your help!)
"I would not use normal distribution to model weekly income since the data is positively skewed with a coefficient of 0.757 whilst a normal distribution is symmetrical, i.e. it has no skew.
Also the probability of 240<=y<=400 = 0.52
0.52 calculated via (frequency from 240-400 / Sum of f)
which is quite far from her value of 0.404, showing her model is unreliable.
Therefore Katie's suggestion is bad and wrong. Even here [sic] mean (320) and standard deviation (150) are not the true values of the data which are 316 and 157 respectively, however they are close"

Yeah look like I'm not getting any extra marks, I won't remark.

I wonder if that 4c question was what everybody screwed up on - highest mark in my class was 94 (I was second) so I'm guessing that was the question everyone dropped marks on.

From the papers I've reviewed with students
4c (4 marks) - missing the conditional probability
5f (2 marks) - commenting only on skewness, ignoring the part e and that data in the table
6f (4 marks) - not picking up that she can choose either dice depending on the outcome of the coin toss

Think students may have got used to the predictability of past S1 papers.

I can understand the second two, but normal distribution AND conditional probability in one question? I've never seen nor done an example of that.

Agreed, after some criticism that papers are too predictable (and that some papers can be done just by crunching numbers through formulae with little understanding) I think they are injecting a little bit more 'thinking' challenge to test the more capable candidates.

From the papers I've reviewed with students
4c (4 marks) - missing the conditional probability
5f (2 marks) - commenting only on skewness, ignoring the part e and that data in the table
6f (4 marks) - not picking up that she can choose either dice depending on the outcome of the coin toss

Think students may have got used to the predictability of past S1 papers.