Re: [R] [newbie] Want to perform some simple regressions.

From: Duncan Murdoch <murdoch_at_stats.uwo.ca>
Date: Sun 28 Aug 2005 - 20:39:36 EST

Sean O'Riordain wrote:

> Hi Thomas,
> I'm not an expert - so I might use incorrect terminology, but
> hopefully you'll get the picture!
> 
> Assuming that you've got your data in a .CSV file, you'd first read in
> your data, where the first three lines might look like...
> 
> x,y
> 0,2.205954909440447
> 1,8.150580118785099
> 
> # load the info into a data.frame called mydata
> mydata <- read.csv("mycsvfile.csv",header=TRUE)
> # now "attach" to this data.frame, so that the internal
> attach(mydata)
> # now do the regression and store it in the object "myregr"
> myregr <- lm(y~x)

Thomas's model was

y = (a*x + b) * ln (c*x + d) + error

which is not a linear model. He'll need to use nonlinear regression (the nls function), which is a little more complicated. I'd recommend geting local help from a statistician to get it right.

Duncan Murdoch

> # print out the info from myregr
> myregr
> # to get more info from myregr use the summary() method...
> summary(myregr)
> 
> There is an enormous quantity of documentation available, though it
> takes a little while to learn to use it properly and get the full
> effectiveness from it...
> 
> I strongly recommend that you read the "Posting Guide"
> http://www.R-project.org/posting-guide.html
> which will help you.
> 
> For more information, have a look at the introduction to R; which is a
> tad terse in places - so read it slowly :-)
> 
> Have a look also at the other documentation 
> http://www.r-project.org/other-docs.html
> 
> In particular I'd recommend John Maindonalds online book at
> http://cran.r-project.org/other-docs.html
> 
> cheers!
> Sean
> 
> On 28/08/05, Thomas Baruchel <archaiesteron@laposte.net> wrote:
> 

>>On Sun, Aug 28, 2005 at 09:48:15AM +0200, Thomas Baruchel wrote:
>>
>>>Is R the right choice ? Please, could you step by step show me
>>>how you would do on this example (data below) in order to let me
>>
>>I forgot my data :-(
>>
>>0 2.205954909440447
>>1 8.150580118785099
>>2 15.851323727378597
>>3 22.442795956953574
>>4 29.358579800271354
>>5 36.46060528847214
>>6 43.7516923268591
>>7 51.223688311610026
>>8 58.86610205087116
>>9 66.66821956399055
>>10 74.61990268453171
>>11 82.71184423952718
>>12 90.93560520053082
>>13 99.28356700194489
>>14 107.74885489906521
>>15 116.3252559311549
>>16 125.00714110112291
>>17 133.78939523822717
>>18 142.6673553086964
>>19 151.63675679510055
>>20 160.69368733376777
>>21 169.834546691509
>>22 179.05601219606618
>>23 188.35500882314003
>>24 197.72868324657364
>>25 207.17438125936408
>>26 216.68962806440814
>>27 226.2721110130965
>>28 235.9196644372003
>>29 245.63025627606442
>>30 255.40197624835042
>>31 265.23302535689197
>>32 275.12170654792556
>>33 285.06641637317705
>>34 295.0656375259694
>>35 305.1179321414606
>>36 315.2219357669857
>>37 325.3763519217964
>>38 335.5799471767038
>>39 345.8315466936063
>>40 356.13003017290697
>>41 366.4743281636434
>>42 376.8634186969678
>>43 387.2963242085816
>>44 397.77210871999046
>>45 408.2898752521091
>>46 418.8487634479048
>>47 429.44794738349896
>>48 440.08663354951693
>>49 450.76405898653184
>>50 461.479489560246
>>51 472.2322183636179
>>52 483.02156423451737
>>53 493.84687037869463
>>54 504.707503088911
>>55 515.6028505520102
>>56 526.5323217365377
>>57 537.4953453542455
>>58 548.4913688894654
>>59 559.5198576909147
>>60 570.5802941210067
>>61 581.6721767581994
>>62 592.7950196483222
>>63 603.9483516011882
>>64 615.1317155291274
>>65 626.3446678243708
>>66 637.5867777724806
>>67 648.8576269992603
>>68 660.1568089487967
>>69 671.4839283904737
>>70 682.838600952985
>>71 694.2204526835204
>>72 705.6291196304554
>>73 717.0642474479981
>>74 728.5254910213728
>>75 740.0125141112243
>>76 751.5249890160294
>>77 763.062596251391
>>78 774.6250242451752
>>79 786.2119690475241
>>80 797.8231340548524
>>81 809.4582297469931
>>82 821.1169734367211
>>83 832.7990890309349
>>84 844.5043068028273
>>85 856.2323631744205
>>
>>Regards,
>>
>>--
>>Thomas Baruchel
>>
>>______________________________________________
>>R-help@stat.math.ethz.ch mailing list
>>https://stat.ethz.ch/mailman/listinfo/r-help
>>PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
>>
> 
> 
> ______________________________________________
> R-help@stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html

______________________________________________
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Sun Aug 28 20:50:10 2005

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