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Дата изменения: Tue Jan 26 01:52:59 1999 Дата индексирования: Mon Oct 1 23:49:25 2012 Кодировка: Поисковые слова: trees |
In class exercise. Class do the following:
In the
Sacred Box of Sampling there are 170 numbers which
define this Intrinsic Distribution .
The point of the in class exercises is to demonstarte that a
random sampling process done for an intrinsic distribution which
is normally distributed (i.e. a bell curve)
will provide a robust estimate of the mean and dispersion after
just a small number of samples.. While
this can be proved with calculus (and in statistics is known as
the
Central Limit Theorem), the in class example is the probably the best
means of demonstrating this.
For this sample as a whole:
The point of the demo in the class is to see how close we can come
to recovering this population mean and dispersion from the sample
mean and dispersion.
In general, we use statistics as a means of characterizing the nature of some sample on the basis of a few key indicators.
The first indicator is known as The Sample Mean:
23 | 33 | 43 | 25 | 37 | 51 |
---|
The Mean age of the population in the store is 35 years. Does that tell me much?
In general, the dispersion is a more important quantity than the sample mean. The dispersion represents the range of the data about the mean value. Understanding the role of dispersion is the most critical aspect of understanding and interpreting statistical sampling data.
So let's take a look at how dispersion plays such a critical role.