Examples of using Sample mean in English and their translations into Thai
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Colloquial
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Ecclesiastic
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Ecclesiastic
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Computer
We figured out the sum of squares between each data point and its central tendency, its sample mean, we figure out and we totaled it all up, we got 6 for the sum of squares within.
But when we talk about the sample mean and the sampling distribution of the sample mean which we're going to talk more and more about over the next few videos, normally the sample refers to the set of samples from your distribution.
So at least for your sample you say"My sample mean is 2 hours of television." It's an estimate, it's a statistic that is trying to estimate this parameter, this thing that is very hard to know.
Now the mean value of this, the mean-- let me write it-- the mean of the sampling distribution of the sample mean, this x bar-- that's really just the sample mean right over there-- is equal to, if we were to do this millions and millions of times.
So for every data point in our sample, so we have n of them we take that data point, from it we subtract our sample mean square it and then divide by the number of data points that we have.
I can't say the equal now, because over here if we knew this, if we knew this parameter of the sampling distribution of the sample mean, we could say that it is 95.4.
That is being calculated for each of our data points, so starting with our first data point in each of our samples, going to nth data point in each of the samples, we're taking our data point, subtracting out the sample mean squaring it and dividing the whole thing not by n-1, but by lower case n.
So let's say we're looking at sample means.
So I'm plotting the actual frequency of the sample means.
So just here based on our sample proportions, or our sample means, it looks like there is a difference.
The standard deviation of our distribution of the difference of the sample means is going to be equal to the square root of the variance of our first population.
Well the standard deviation of the differences of the sample means is going to be equal to, and we saw this in the last video-- in fact, I think I have it right at the bottom here-- it's going to be equal to the square root of the variances of each of those distributions.
Or, another way of saying it is, if we think about the mean of the distribution of the difference of the sample means, and we focused on this in the last video, that that should be equal to zero.
Well how do we calculate the sample mean.
Find out how far it is from our sample mean.
Let's say we get some sample mean out here.
So what was the sample mean that we actually got?
And it doesn't apply just to taking the sample mean.
It is a sample from the sampling distribution of the sample mean.
So in this case, your sample mean might be right here.