Recent content by Josh S Thompson

I'm talking about the variance of your sample. Like you have a sample, some numbers, and you compute the variance of these numbers. There is no other way to make this clear. Marne Math I'm not talking about the clt, ok stop bringing up stuff about the central limit theorem.

You use t-distribution because it is more accurate than the normal distribution when the variance of the sample is random, which it always is, you would only use the normal distribution for x-bar if the variance was the same for all of your samples. You don't know what the heck you're talking...

I mean the variance of the sampling distribution of the mean, when the variance of the population is known, would shrink, when you take samples of a large number. And my question my question remains: why would the distribution of the sample mean with an unknown population be normal, while the...

I just mean the variance approaches 0. I'm saying shouldn't the sample variance be more closely approximated by the normal distribution because you take sums of standard normal RVs while for the mean it could be any distribution. And like why is it dumb to say that if the sample size is very...

Ok thank you very much ; I just don't really understand sample variance I thought it was supposed to be more accurate than x bar but you say they are both normal. And one more question; if sigma is known the distribution of x bar approaches normal with no variation but if you do not know...

Ok thank you I appreciate the help but I still think you can use moments of a sample to determine the spread of the data

Does it have a cdf or something because that's not that good of a reason but what do I know.

And what do you use it for. I'm pretty sure they only use it in academia for sum reason

how do you derive that distribution

Why would you be working with exponential functions of a random variable

But I don't understand if you use the t distribution to find the probability of the sample mean taking on some value why is the sample mean normally distributed

I just don't really get why you say the sample mean is the population mean but then you can't do that for the population variance can you please explain the t distribution please

I thought t distribution was the distribution of the sample mean if the variance is unknown. But how can you have a distribution of the sample mean if you do not know the population mean or the population variance

So my understanding of the T distribution is that if you do not know the variance of a population you estimate the distribution of the mean with the T distribution. But I am not sure about this because if you know the variance of the population, law of large numbers shrinks the variance...