The Student Room Group
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>

AQA Statistics 1 MS1B Unofficial Mark Scheme

This is my answers to the S1 Exam this morning, please correct me if some are incorrect. I hope this helps! :smile:

1.

a) r = 0.498 (2 Marks)

b) There is a moderate positive correlation between ... and ... (2 Marks)

2. a) mean = 68.3 variance = 2.46 and 2.42 was also allowed (4 Marks)

b) mean = 2.69 variance = 3.81 x 10^-3 (2 Marks)

3.

a) Complete the table (2 Marks)

b) i) 0.56 ii) 0.20 (3 Marks)

c) i) 0.25 ii) 0.90 (5 Marks)

d) 0.084 (4 Marks)

4.

a) Plot the remaining four points (2 Marks)

b) i) y = 0.405x + 1.3 (6 Marks)

ii) Explain this in context of the question (3 Marks)

c) when x = 15, y = 7.4 (1 Mark)

d) i) Residual = -0.6 (2 Marks)

ii) The residuals only show the connection between the values of y predicted by the line of regression and the actual values of y. Itdoes not look at the relationship between x and y or the sum of the residuals will equal 0 (1 Mark)

5.

a) i) 0.871 ii) 0.309 iii) 0.191 (6 Marks)

b) i) 1.175 (2 Marks)

ii) mean = 9.06 and standard deviation = 0.162 (4 Marks)

6. a) i) 0.695 ii) 0.879 iii) 0.562 iv) 0.131 (9 Marks)

b) 0.0478, It is assumed that the sample is random (4 Marks)

7. a) 0.0418 (4 Marks)

b) i) 304.6 +- 2.2 = [302.4, 306.8] (4 Marks)

ii) First claim is likely correct, as 300 is below the lower limit of the confidence interval

Second claim is very likely to be incorrect as the mean minus one standard deviation is below 300 (4 Marks)
(edited 8 years ago)

Scroll to see replies

Got the same apart from residual 1 mark, and messed up CI
wouldn't the second claim be false since the mean - 4sigma/sqrtn is > 300
Reply 3
Avatar for Jupers
Jupers
5
When explaining the regression line did anyone say 'when 0 tiles, 1.3 hours' or whatever it was. (Intercept) as that makes no sense but I didn't know what else to put
Reply 4
Avatar for amyrah
amyrah
2
I wrote the residual as -0.5... wiIl there be like an interval of correct answers?
Reply 5
Avatar for amyrah
amyrah
2
Original post by Jupers
When explaining the regression line did anyone say 'when 0 tiles, 1.3 hours' or whatever it was. (Intercept) as that makes no sense but I didn't know what else to put


I wrote that but I had like 2 mins left I put down some rubbish about 1.3 hours set up time, organising tools... LOL.
Original post by Jupers
When explaining the regression line did anyone say 'when 0 tiles, 1.3 hours' or whatever it was. (Intercept) as that makes no sense but I didn't know what else to put


I said the time it takes to climb up the ladder onto the roof


Posted from TSR Mobile
Reply 7
Avatar for amyrah
amyrah
2
What was the calculation for 3d?
Reply 8
Avatar for Mmmmmmw
Mmmmmmw
1
Can someone put up how much each question and part was worth pretty please
(edited 8 years ago)
Reply 9
Avatar for Jupers
Jupers
5
Original post by EconPhyMaths
I said the time it takes to climb up the ladder onto the roof


Posted from TSR Mobile


1.3 hours to climb a ladder
Must be the Empire State building
Reply 10
Avatar for saad97
saad97
2
Original post by amyrah
What was the calculation for 3d?


It was (p1/0.80 x p2/0.79 x p3/0.78) x 6 I think?


Posted from TSR Mobile
Reply 11
Avatar for Jupers
Jupers
5
Original post by saad97
It was (p1/0.80 x p2/0.79 x p3/0.78) x 6 I think?


Posted from TSR Mobile


Denominators were all .8 as probability independent day to day
Reply 12
Avatar for tamcat
tamcat
10
what do you think grade boundaries will be like?
last years was 65/75 for A
Does anyone have an unofficial mark scheme for stats 1a this morning?
I think 7a is 0.0416 instead of 0.0418.
Reply 15
Avatar for nahweh
nahweh
2
Original post by amyrah
I wrote that but I had like 2 mins left I put down some rubbish about 1.3 hours set up time, organising tools... LOL.


haha i put the same thing. makes sense though i think?
Reply 16
Avatar for saad97
saad97
2
Original post by Jupers
Denominators were all .8 as probability independent day to day


Oh don't say that :frown: :frown:
What about multiplying by 6?


Posted from TSR Mobile
Reply 17
Avatar for jjsnyder
jjsnyder
OP
10
Original post by antrum95
I think 7a is 0.0416 instead of 0.0418.


Might be a typo, can anyone else confirm?


Posted from TSR Mobile
For 2)b) I think the variance did not change
Reply 19
Avatar for amyrah
amyrah
2
Original post by jjsnyder
Might be a typo, can anyone else confirm?


Posted from TSR Mobile


What was the question?

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you