[R] [spam] t.test confidence interval

[Peter Dalgaard]

Adrian Dusa <dusa.adrian at gmail.com> writes:

> Hi,
> 
> I'm using R for some undergraduate lectures, reaching the t tests.
> No matter what conf.level one specifies in the syntax, the output always shows 
> the 95 percent confidence interval.

That's just not true in my version of R. 

>  t.test(extra ~ group, data = sleep, conf=.8)

        Welch Two Sample t-test

data:  extra by group
t = -1.8608, df = 17.776, p-value = 0.0794
alternative hypothesis: true difference in means is not equal to 0
80 percent confidence interval:
 -2.7101645 -0.4498355
sample estimates:
mean in group 1 mean in group 2
           0.75            2.33



> Is it possible to alter the function somehow, to report the CL percent 
> confidence interval?

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
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