Re: very basic question- t statistic

On Sat, 22 Oct 2005 18:00:13 EDT, Thomas <Thomasravenelli@xxxxxxxxxxx>
wrote:

> I will rephrase the question. i have around 28 years of data
> for each year I calculate the probability of occurence of an event (i.e the probability of an event occuring during one year ) .Let me Call it PrA
> at the end i take the average of these probabilities sum PrA/28 and report the average (I will call it MeanA) . My question is how to report a t test for MeanA? what r the dregrees of Freedom?

The most common thing called a t-test is a test to compare
two means. You do not have two groups.

Another use of the t-statistic is to compare a value, such
as a regression coefficient, to zero -- by dividing the
coefficient by its standard error. You do not have any
coefficient that you would expect to be zero.

I do not see where you have anything that can use a t-test.
What made you think you wanted a t-test?

--
Rich Ulrich, wpilib@xxxxxxxx
http://www.pitt.edu/~wpilib/index.html
.

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