[R] ski.mack test in R

Sarah Goslee
Fri, 23 Aug 2019 13:46:02 -0000

Hi Sophie,

It's good form to reply to the list, not directly to me - I'm not able
to help people individually. It's also good form to put the necessary
info directly into your email, rather than expecting people to open
attachments (which the mailing list might not even allow, depending on
format).

However, your problem is very simple:

You need to load a package before using functions from it.

Ski.Mack() is not found because you first need to do

library(Skillings.Mack)

to make it available to your R session.

(Assuming you've installed the package; if not

install.packages("Skillings.Mack")

will do that for you.

I strongly, strongly suggest that you read one of the good
introductions to R out there, possibly even the one that comes with R,
and is also available here:

https://cran.r-project.org/doc/manuals/r-release/R-intro.pdf

That you've had this problem shows that you don't understand the very
basics of how to use R, so you should familiarize yourself with it
first.

Best,
Sarah

On Fri, Aug 23, 2019 at 6:24 AM Sophie Bleke <sophie.bleke01 at gmail.com>
wrote:
>
> Dear Sarah,
>
> Thank you for you kind and quick response.
>
> I attach the PDF in which I found the ski.mack instructions. This file is
available online.
> I also attach some toy data, on which I am trying to perform the ski.mack
test.
> Please also find attached a txt. file in which you can find the output of
str(a) and error message of ski.mack(a) etc.
>
> I would be very grateful to hear back from you or the list.
>
> With all my best,
> Sophie
>
> Am Di., 20. Aug. 2019 um 19:18 Uhr schrieb Sarah Goslee <sarah.goslee at
gmail.com>:
>>
>> Hi Sophie,
>>
>> We don't have enough information to help you.
>>
>> You DON'T need to type in the data for your test - that's how
the
>> package authors are creating a reproducible example for you.
>>
>> But you do need to have your data in the correct format, and we have
>> no idea what your a looks like.
>>
>>
>> a <- read.table(file.choose(), header=T) # good
>> # attach(a) # don't do this
>> a<-as.matrix(a)
>>
>> library(Skillings.Mack) # you forgot to tell us where you got the
>> function you're using
>>
>> a needs to be "Either a numeric vector of data values, or a data
>> matrix. If a matrix is used, columns and rows are correspondent to
>> blocks and treatments (groups), respectively."
>>
>> Since your a is a matrix, then it should be the latter. Is that what
you have?
>>
>> You say that
>>
>> Ski.Mack(a)
>>
>> "doesn't work." That isn't enough for us to help.
What error message
>> do you get? We need specifics about what "doesn't work"
means.
>>
>> We also need a reproducible example, possibly with toy data like the
>> package authors used
>>
[.https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example]
>> The output of
>>
>> str(a)
>>
>> would also be very helpful.
>>
>> Sarah
>>
>> On Tue, Aug 20, 2019 at 12:02 PM Sophie Bleke <sophie.bleke01 at
gmail.com> wrote:
>> >
>> > Dear R-Help List,
>> >
>> > For part of my data, which I analyse with Friedman.test, there is
data
>> > missing, which is a normal result of the experimental setup. If I
am
>> > correct, I need to use the Ski.Mack test in R for it.
>> >
>> > Normally, I read my data in for Friedman or post hoc Wilcoxon like
below:
>> >
>> > a <- read.table(file.choose(), header=T)
>> >
>> > attach(a)
>> > a<-as.matrix(a)
>> >
>> > friedman.test(a)
>> >
>> > I tried to replace the friedman line with your ski.mack command,
but it is
>> > not getting me where I need to get.
>> >
>> > Ski.Mack(a, simulate.p.value = TRUE, B = 1000)
>> >
>> > or
>> >
>> > Ski.Mack(a)
>> >
>> > Both don't work.
>> >
>> > Is there as simple command way, as above, to read out the ski.mack
test
>> > from my txt file, without manually typing all the data points as
rows and
>> > colums in the R console, which is recommended in the ski.mack
author's
>> > online PDF? It's a lot of data and manually inputting rows and
colums and
>> > data points won't be doable in this case.
>> >
>> > I would be very grateful to hear of an elegant short solution,
similar to
>> > the friedman command / read-in lines above.
>> >
>> > Sophie
>> >
>>
>>
>> --
>> Sarah Goslee (she/her)
>> http://www.numberwright.com