[BlindRUG] Some Questions

[Ensor, Tyler]

I thought I would add my two cents on assessing normality. Maybe this
will help someone. I can't see a Q-Q plot, and used to use hypothesis
tests such as the Shapiro-Wilk or Kolmogorov-Smirnov. However,
statisticians generally find these tests unhelpful, as they are too
conservative with small sample sizes (i.e., very nonnormal data will
still be deemed normal) and too liberal with large samples (i.e., very
small deviations from normality will push the p value into the
rejection region).

The approach I've since adopted is to look at the values of skewness
and kurtosis. Skewness and kurtosis both have a standard error
associated with them. If the skewness and kurtosis values are both
within -2 or +2 standard errors of 0, then you can conclude that data
are normal. This isn't a perfect approach, as it is somewhat
arbitrary, but inspecting a Q-Q plot also lacks objectivity.

Tyler

On 6/12/15, Voica Gavrilut via BlindRUG <blindrug at nfbnet.org> wrote:
> Hello,
>
>>    1. Auto Load
>>    I want BrailleR package to be loaded automatically when starting R.
>> How can I do?
> For example I use the config file that already exists in the R
> installation - the R_HOME/etc/Rprofile. in this file I added a
> function to change my working directory and to load some of my useful
> scripts:
> .First <- function() {
> setwd("my_path")
> source("my_script1.r")
> #library("BrailleR")
> }
> Take care to the dot before the function name and the first letter
> capitalized, are part of the R config requirements.
>
> Good luck
> --
> G.Voica
>
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>
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> http://R-Resources.massey.ac.nz/lurn/front.html
>