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    help with 2014 question 16cii
    and also 2015 paper question 8c edexcel plz
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    helloooooooooooooooooo?
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    Damn, I can't really help you because im doing aqa. Tell me what you got stuck on and ill try to help.

    I have my stats test tomorrow.
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    (Original post by hjfxfykk)
    help with 2014 question 16cii
    and also 2015 paper question 8c edexcel plz
    2014 paper was my mock and I got the mark for saying:
    "The zoologist is roughly correct as about 95% of the elephants were between 47 and 167 and there is one single modal class in roughly the centre of that data."
    Our maths teacher has a bit of a tendency to go off the mark scheme though so that could be wrong

    2015 paper I did last night lol so marking might have been a bit erratic
    there were marks for saying
    -number the people at her college (separately by gender)
    - use a computer to generate a random number
    -the sample should be representative of the population (proportional genders)
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    (Original post by Lemur14)
    2014 paper was my mock and I got the mark for saying:
    "The zoologist is roughly correct as about 95% of the elephants were between 47 and 167 and there is one single modal class in roughly the centre of that data."
    Our maths teacher has a bit of a tendency to go off the mark scheme though so that could be wrong

    2015 paper I did last night lol so marking might have been a bit erratic
    there were marks for saying
    -number the people at her college (separately by gender)
    - use a computer to generate a random number
    -the sample should be representative of the population (proportional genders)
    for 2014 can u plz explain cuz im freaking out right now!!!!!!!!!!!!!!
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    (Original post by hjfxfykk)
    for 2014 can u plz explain cuz im freaking out right now!!!!!!!!!!!!!!
    I'm seriously freaking out, having found several topics in the last couple of days I'd never heard of! (our teacher hates statistics so didn't bother teaching it to us)
    Looking back at this paper I don't actually understand why I got it right tbh but basically in the previous question you work out 2 standard deviations from the mean is between 47 and 167. Then from the histogram you can see that there aren't very many outside that, if any so you can say that roughly 95% are between that range. Plus from the histogram you can see the distribution is roughly normally distributed as well particularly with the central modal class.

    I hope that makes sense, I'm really bad at explaining things!
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    QUICK QUESTION GUYS !!You know for the trend line and the seasonal moving averages. You know the question ( usually the last part ) it says estimate the .... for 2008 quarter 2. Use your answer to part (d). How do you know whether to add it or take it away ?!

    Also another question - when drawing the line of best fit do you draw it through the mean ?
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    (Original post by Lemur14)
    I'm seriously freaking out, having found several topics in the last couple of days I'd never heard of! (our teacher hates statistics so didn't bother teaching it to us)
    Looking back at this paper I don't actually understand why I got it right tbh but basically in the previous question you work out 2 standard deviations from the mean is between 47 and 167. Then from the histogram you can see that there aren't very many outside that, if any so you can say that roughly 95% are between that range. Plus from the histogram you can see the distribution is roughly normally distributed as well particularly with the central modal class.

    I hope that makes sense, I'm really bad at explaining things!
    For the 2014 one I did 107-2 times 30 which gives 47 and then you do 107+2 times 30 which is 167. The 107 is the mean. The 2 comes from the 95% and 30 the S.D which they mention on the previous question.

    QUICK QUESTION !!
    You know for the trend line and the seasonal moving averages. You know the question ( usually the last part ) it says estimate the .... for 2008 quarter 2. Use your answer to part (d). How do you know whether to add it or take it away ?!

    Also another question - when drawing the line of best fit do you draw it through the mean ?
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    Yes, if you are supposed to find the mean point, or they give you a mean point. Then the best line of fit has to go through the mean point.
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    (Original post by stoyfan)
    Yes, if you are supposed to find the mean point, or they give you a mean point. Then the best line of fit has to go through the mean point.
    Oh ok thank you. What about this one ?

    You know for the trend line and the seasonal moving averages. You know the question ( usually the last part ) it says estimate the .... for 2008 quarter 2. Use your answer to part (d). How do you know whether to add it or take it away ?!
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    (Original post by nisha.sri)
    Oh ok thank you. What about this one ?

    You know for the trend line and the seasonal moving averages. You know the question ( usually the last part ) it says estimate the .... for 2008 quarter 2. Use your answer to part (d). How do you know whether to add it or take it away ?!
    Depends whether the point you are meant to find is above or below the trend line.
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    (Original post by nisha.sri)
    Oh ok thank you. What about this one ?

    You know for the trend line and the seasonal moving averages. You know the question ( usually the last part ) it says estimate the .... for 2008 quarter 2. Use your answer to part (d). How do you know whether to add it or take it away ?!
    Do you have any example? I should be able to help
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    (Original post by fruit shoot)
    Depends whether the point you are meant to find is above or below the trend line.
    So if it's below then you take it away?!

    (Original post by Jacktheslipper)
    Do you have any example? I should be able to help
    2014 paper question 13b thank you
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    (Original post by nisha.sri)
    So if it's below then you take it away?!

    Yeah and if it's above you add it on.
 
 
 
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