[R] Trying to get around R

Tue Nov 20 07:07:23 CET 2007

Loren,

There's a good reason for replying to the list, rather than just to you 
personally: to let other readers of the list see the response, so that 
they don't duplicate it. Your original posting certainly looked like 
homework questions to me. This impression was reinforced by the fact 
that the posting was anonymous: this is surely a breach of general 
netiquette, rather than an R newbie error?

Students do attempt to get people on this list to do their homework for 
them. It is important, for the integrity of their degrees, that we 
minimise the occurrence of this. Regular contributors to this list (and 
I am not one) perform a huge public service. we should all be grateful 
for this.

Ted Catchpole.

 Visiting Fellow
 Univ of New South Wales at ADFA, Canberra, Australia
    _	  and University of Kent, Canterbury, England
   'v'	  - www.pems.adfa.edu.au/~ecatchpole          
  /   \	  - fax: +61 2 6268 8786		   
   m m    - ph:  +61 2 6268 8895             

Loren Engrav wrote on 11/20/2007 04:43 PM:
> I am a newbie to R and Bio emails and
>
> It is clear that newbies make "mistakes", I made several which were pointed
> out and I am trying to fix them, and as I fix one I make another, in time
> perhaps I will "know it all", but if it is like surgery, I will make
> mistakes until I retire
>
> But the response of the "old-timers" to these mistakes seems arrogant and
> cruel and "off putting" and does NOT encourage more participation. In fact
> it takes "real stuff" to continue after this putdown and that putdown.
>
> There are 3,783 links to posting guidelines, which took 1.5 hours to find
> and read and understand.
>
> Why not a link on how the mistakes of the newbies will be dealt with?
>
> Or a kindly response from the moderator personal to the newbie rather than
> to the entire world?
>
> Or a kindly general response as from Ben Bolker to my last infraction which
> was "You might have better luck with this on the Bioconductor mailing list
> ..."
>
> Rather than to the universe...
> "Using the wrong list: this is for R-sig-mac, and the topic occcurred
> there recently."
>
> All in an effort to encourage promote useful and increasing exchange
> participation
>
> Or not....
>
> Loren Engrav, MD
> Univ Washington
>
>
>   
>> From: Julian Burgos <jmburgos at u.washington.edu>
>> Date: Mon, 19 Nov 2007 10:44:49 -0800
>> To: Epselon <jazzyazza at hotmail.com>
>> Cc: <r-help at r-project.org>
>> Subject: Re: [R] Trying to get around R
>>
>> Hello Epselon (if that is your name),
>>     
>
> This sounds like homework questions.
>   
>> From the R-help posting guide: 
>>     
> "Basic statistics and classroom homework:
>   
>> R-help is not intended for 
>>     
> these."
>
> If you have a specific question on R
>   
>> coding, do ask it (and provide 
>>     
> reproducible code).  But you should not expect
>   
>> for people on the list to 
>>     
> do your homework for you.  That is a big
>   
>> no-no.
>>     
>
> Cheers,
>
> Julian
>
>
>   
>>> Epselon wrote:
>>>       
>> I have three problems I am trying to
>>     
>>> simulate, that I am having difficulty
>>>       
>> getting around with.
>>
>> Problem 1.
>>     
>> I want to determine the 85 percentile (the x value for which the sum of
>>
>>     
>>> probabilities becomes 0.85) of the following distributions (two binomials
>>>       
>>> and a Poisson with rate Lmbda= np of the two binomials): X ~B(10, 0.3),
>>>       
>>> Y~P(3) , 
>>>       
>> Z~B(30, 0.1). I want to show that  that Y is a good approximation
>>     
>>> for Z but
>>>       
>> not for X...(by examining these distributions for few
>> different
>>     
>>> percentiles)
>>>       
>> Problem 2:
>> For a binomial distribution X ~ B(20, 0.4), I
>>     
>>> want to use R to calculate
>>>       
>> P{|X - μ| < 2} and verify that it is near or
>>     
>>> larger than 0.95. (Hint from
>>>       
>> the text book: Since μ = 8 and   2.3 then
>>     
>>> you 
>>> may want to read the
>>>       
>> weights, or probabilities, of the values 6:10, into a
>>     
>>> vector v and then use
>>>       
>> the command sum(v) to
>> calculate the sum.) Repeat
>>     
>>> this for another set of parameters of your
>>>       
>> choice.
>>
>> Problem 3:
>> Draw a
>>     
>>> sample of size 10, from a Poisson with Lambda= 5, and calculate the
>>>       
>> mean
>>     
>>> and 
>>> the standard deviation of this sample, Repeat this calculation with
>>>       
>> size 20
>>     
>>> and 30 and demonstrate
>>>       
>> that ¯X gets closer to μ as the sample size
>>     
>>> increases.
>>>       
>> Thanks.
>>
>> I would appreciate it if someone accompanied the
>>     
>>> codes with a brief
>>>       
>> explanation so I can be able to replicate it
>>     
>>> myself.
>>>       
>
> ______________________________________________
> R-help at r-project.org
>   
>>> mailing list
>>>       
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the
>   
>>> posting guide http://www.R-project.org/posting-guide.html
>>>       
> and provide
>   
>>> commented, minimal, self-contained, reproducible code.
>>>       
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>   