sigma

  1. P

    error variance estimation with sample-weights

    Hello, I am using data which include a (sample-)weight for each observation, i.e. the data is from a survey that has weights to make the sample representative for the US-population. I perform OLS to get some coefficients and I am trying to estimate the error variance...
  2. L

    Adjust for overdispersion in glm family = binomial (logit) model

    I have an overdispersion problem in my model.. I have the following data: y= succes/fail (%) x= Var1 : Temperature data m1<-glm(cbind(succes,fail)~Var1, data=data, family = binomial(logit)) Call: glm(formula = cbind(succes, fail) ~ Var1, family = binomial(logit), data = data)...
  3. E

    Normal distribution

    Hi all, I'm generating a random normal distribution and i don't control the mu and sigma (its a matlab function that i need to use because the ratio between the numbers). Is there any way to change the mu and sigma and still keep the same ratio between the numbers in the vector? I hope you...
  4. T

    Why is a Dynkin system not a Pi-system?

    This appears to be the only difference between a sigma-algebra and a Dynkin system: Sigma-algebra is closed under countable union Dynkin system is closed under countable union of disjoint sets This seems to result in the D-system not being a pi-system (while the sigma-alg is). Why...