S2 question Sampling

    • Thread Starter
    Offline

    2
    ReputationRep:
    Could I have help with 6a please?Name:  IMG_0472.jpg
Views: 33
Size:  486.8 KBAttachment 583034583036
    Attached Images
     
    Offline

    3
    ReputationRep:
    (Original post by swagmister)
    Name:  IMG_0472.jpg
Views: 33
Size:  486.8 KBAttachment 583034583036Could I have help with 6a please?
    Unless you've misread the value from the table I see nothing wrong with your working
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by SeanFM)
    Unless you've misread the value from the table I see nothing wrong with your working
    The answers say it's 0.155 I tried 6b which was a similar question but also got the wrong answer
    Offline

    3
    ReputationRep:
    (Original post by swagmister)
    The answers say it's 0.155 I tried 6b which was a similar question but also got the wrong answer
    Beats me, sorry. I agree with your answer
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by SeanFM)
    Beats me, sorry. I agree with your answer
    Maybe the textbook is wrong? I'll ask my teacher tomorrow, thanks for taking a look anyway 👍
    Offline

    3
    ReputationRep:
    Shouldn't there be a continuity correction, since it's a binomial distribution?

    (Original post by swagmister)
    Could I have help with 6a please?Name:  IMG_0472.jpg
Views: 33
Size:  486.8 KBAttachment 583034583036
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by NotNotBatman)
    Shouldn't there be a continuity correction, since it's a binomial distribution?
    Idk that would make sense but I didn't use it in any of the other questions that similar and got the right answer
    Offline

    3
    ReputationRep:
    (Original post by swagmister)
    Idk that would make sense but I didn't use it in any of the other questions and got the right answer
    Try it again with a continuity correction and see if you get the answer in the textbook.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by NotNotBatman)
    Try it again with a continuity correction and see if you get the answer in the textbook.
    I got 0.9292 Name:  image.jpg
Views: 34
Size:  479.8 KB
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by NotNotBatman)
    Try it again with a continuity correction and see if you get the answer in the textbook.
    Do you not need a continuity correction because the means and sampling mean aren't discrete?
    Offline

    3
    ReputationRep:
    (Original post by swagmister)
    I got 0.9292 Name:  image.jpg
Views: 34
Size:  479.8 KB
    You'd need to apply the continuity correction to the total score (mean multiplied by number of throws) and then divide by 70.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by NotNotBatman)
    You'd need to apply the continuity correction to the total score (mean multiplied by number of throws) and then divide by 70.
    So ((35/12)+0.5)/70??
    Offline

    3
    ReputationRep:
    (Original post by swagmister)
    So ((32/15)+0.5)/70??
    Where's 32 and 15 coming from?

    You do 3.3 x 70 = 231, then apply the continuity correction and divide by 70, then you find your standardized z value.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by NotNotBatman)
    Where's 32 and 15 coming from?

    You do 3.3 x 70 = 231, then apply the continuity correction and divide by 70, then you find your standardized z value.
    Oh I was taught to add or minus 0.5 onto x where eg. P(X<x), I got 0.1723 this timeName:  image.jpg
Views: 26
Size:  419.6 KB
    Offline

    3
    ReputationRep:
    (Original post by swagmister)
    Oh I was taught to add or minus 0.5 onto x where eg. P(X<x), I got 0.1723 this timeName:  image.jpg
Views: 26
Size:  419.6 KB
    In this case it's different because it's a mean.

    You've done the continuity correction the wrong way around; it's less than x, not less than or equal to, so subtract 0.5.

    230.5/70 = 3.29...
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by NotNotBatman)
    In this case it's different because it's a mean.

    You've done the continuity correction the wrong way around; it's less than x, not less than or equal to, so subtract 0.5.

    230.5/70 = 3.29...
    Oh right I haven't learnt that yet, oh yeah, I got 0.1585
    • Thread Starter
    Offline

    2
    ReputationRep:
    Nevermind I read the tables wrong
    • Thread Starter
    Offline

    2
    ReputationRep:
    Got 0.155 now!
    • Thread Starter
    Offline

    2
    ReputationRep:
    How come you use the continuity correction in Q6 but not Q5?
    Name:  image.jpg
Views: 26
Size:  400.9 KB


    (Original post by NotNotBatman)
    In this case it's different because it's a mean.

    You've done the continuity correction the wrong way around; it's less than x, not less than or equal to, so subtract 0.5.

    230.5/70 = 3.29...
    Offline

    3
    ReputationRep:
    (Original post by swagmister)
    How come you use the continuity correction in Q6 but not Q5?
    Name:  image.jpg
Views: 26
Size:  400.9 KB
    I'm not sure, I think you should use a continuity correction.
 
 
 
Write a reply… Reply
Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. Oops, you need to agree to our Ts&Cs to register
  2. Slide to join now Processing…

Updated: October 4, 2016
TSR Support Team
Today on TSR
Poll
Would you ever go to a non Russell Group uni?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

Equations

How to use LaTex

Writing equations the easy way

Student revising

Study habits of A* students

Top tips from students who have already aced their exams

Study Planner

Create your own Study Planner

Never miss a deadline again

Polling station sign

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups
Study resources

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.