Help on Expected Frequencies Q2 & 3 - No Quotes

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Assistance is requested for calculating expected frequencies in questions 2 and 3, specifically regarding the Poisson and normal distributions. The user has a grasp on the Poisson expectation but struggles with deriving the normal distribution. To obtain the normal distribution's probability density function (PDF), integration between bin ranges and multiplication by 1000 is suggested. The variance for the Poisson distribution is discussed, with emphasis on understanding possible values and their associated probabilities. The conversation encourages further research for clarity on standard deviation and variance calculations.
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I need help on question 2 and 3. For question 2, I think I got the expectation for Poisson distribution, but I have no idea how to get the normal one. Could someone provide me a formula or something? Thanks a lot!
 
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ongfufu said:
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I need help on question 2 and 3. For question 2, I think I got the expectation for Poisson distribution, but I have no idea how to get the normal one. Could someone provide me a formula or something? Thanks a lot!

Once you have the PDF (Probability distiribution (normal in your case)), you integrate the PDF between the range of each bin and multiply it by 1000. You probably have tables for this in your text. One way you could get the PDF is from the mean and variance.
 
I think the expectation for Poisson is the mean for this. So how would I get the variance? I know its the sum of the square of the possible values multiplied by the probabilities, subtract the mean squared. But what are the possible values and the probabilities?
 
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