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Edexcel S2 Modelling - January 2003

Hi,

I was wondering if anyone could shed some light on this question. I don't understand which parameters or distribution to use for the model in (a):

Screen Shot 2016-02-17 at 17.01.20.png

Reply 1

tiny hobbit

Original post by Euclidean

Hi,

I was wondering if anyone could shed some light on this question. I don't understand which parameters or distribution to use for the model in (a):

Screen Shot 2016-02-17 at 17.01.20.png

Imagine a rod whose length to the nearest cm is 8 cm. Its true length is between 7.5 and 8.5 cm and is equally likely to be anywhere in that range. So you need a continuous uniform distribution (rectangular). Whether you take the difference as being -0.5 to +0.5 or as 0 to 0.5 (ignoring the sign of the difference) doesn't matter as long as you stick with the same thing throughout the question.