Help on Expected Frequencies Q2 & 3 - No Quotes

  • Thread starter Thread starter ongfufu
  • Start date Start date
  • Tags Tags
    Frequencies
AI Thread Summary
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.
ongfufu
Messages
2
Reaction score
0
Untitled.jpg

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!
 
Last edited:
Physics news on Phys.org
ongfufu said:
Untitled.jpg

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?
 
Last edited:

Thread 'Finding the number of ways to arrange identical balls in a circle (3 different colors)'

I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
View full post »

Thread 'Greatest possible value of a constant in polynomial'

Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
View full post »

Similar threads

How to work out expected frequency from normal distribution
Replies
1
Views
10K
Poisson Distribution -- Rental of a number of television sets
Replies
13
Views
2K
Intersection of a circle and a sine curve
Replies
26
Views
689
Basic coin toss problem to get 1 head, but with a different method
Replies
2
Views
2K
Dice Game: 6-sided die vs 20-sided die
2
Replies
53
Views
9K
Solving Plane Equation 3x + 2y -z = 4
Replies
8
Views
2K
I Frequency of prime number gaps according to (p-1)/(p-2)
Replies
2
Views
1K
Expected Value: Bidding for a House
Replies
31
Views
3K
Dividing with indices resulting in incorrect sign
Replies
4
Views
1K
Question about fractions
Replies
10
Views
2K

Hot Threads

Recent Insights

Back
Top