I am in India @ Isehcon... 2012 A cordless extension would end the stream
of electronics adapters and also work on the planeŠ.why don't they invent
a wireless extension cord :)-?
On 10/6/12 1:54 PM, "Steve Simon, P.Mean Consulting" <[log in to unmask]> wrote:
>On 10/6/2012 7:21 AM, Anoop Balachandran wrote:
>
>> I had 2 simple stats questions:
>>
>> *1.* In our lab, we did grip tests and we had both males and
>> females. After the test, we see the average (3 measurements) of the
>> males and females to differ. If so, can we say that there is a
>> difference between male and female grip strength *in our sample *(
>> not trying to generalize to apopulation)? If we say that there is a
>> difference, what if it was just due to chance?
>
>I'm not sure I follow. Do you have three males and three females each
>with one grip strength measurement, or do you have a different number of
>males and females, each of who repeats the grip test three times?
>
>There is a difference in the sample if there is a difference in the
>sample. It requires just looking at the data. If you want to generalize,
>then you need a t-test, assuming one measurement per patient. With three
>measurements per patient, it gets a bit trickier, but you can always
>average the three measurements per patien
>
>>
>> *2.* To use correlations, do we need a normal data? I am trying to
>> compare 2 variables collected from our lab. And I am not trying to
>> infer anything about the population. I just want to see if there a
>> correlation for my variables in my subjects. I have read that
>> correlation is calculated from Z scores so I am guessing it has to be
>> a normal curve.
>
>Computation of a correlation does not require any assumptions about the
>data, but any p-value or confidence interval calculation would require
>this.
>
>But I'm a little bit concerned. Twice now, you've mentioned that you
>don't care to extrapolate beyond the patients in your sample. There are
>settings where extrapolation to a larger population is not interesting
>or important, but they are fairly rare. Unless your sample was very
>special, like the King and Queen of England, I can't imagine why you
>wouldn't be interested in extrapolation.
>
>> Thanks you and sorry for these silly questions
>
>Not a silly question. A silly question would be "Why don't they invent a
>cordless extension cord?"
>
>Steve Simon, [log in to unmask], Standard Disclaimer.
>Sign up for the Monthly Mean, the newsletter that
>dares to call itself average at www.pmean.com/news
>
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