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    Sue throws a fair coin 15 times and records the number of times it shows heads. State the distribution to model the number of times the coin shows a head.

    as n=15 and p=0.5 i said normal, but the mark scheme says binomial.
    surely a coin toss has a normal distribution? or is the answer to these types of question always binomial distribution?
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    (Original post by jbuck100)
    Sue throws a fair coin 15 times and records the number of times it shows heads. State the distribution to model the number of times the coin shows a head.

    as n=15 and p=0.5 i said normal, but the mark scheme says binomial.
    surely a coin toss has a normal distribution? or is the answer to these types of question always binomial distribution?
    its binomial.
    for coin flips its usually always binomial; as it has only 2 outcomes and fits the criteria better.
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    It's a discrete random variable with a uniform rate of occurance, so ofcourse it's binomial - normal is for continous variables.
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    cool, although isnt poisson also a discrete random variable with a uniform rate of occurance?
    i assume the answer would never be poisson though unless they ask like 'what would be a suitable approximation to use'..
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    (Original post by jbuck100)
    cool, although isnt poisson also a discrete random variable with a uniform rate of occurance?
    i assume the answer would never be poisson though unless they ask like 'what would be a suitable approximation to use'..
    It cannot be poisson as it has to satisfy that n is large and p is small
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    (Original post by jbuck100)
    cool, although isnt poisson also a discrete random variable with a uniform rate of occurance?
    i assume the answer would never be poisson though unless they ask like 'what would be a suitable approximation to use'..
    It can't be poisson as the variance and mean will be far away from eachother.
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    awesome
 
 
 
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