[R] linear regression

[Dennis Murphy]

Hi:

Try something like this, using dat as the name of your data frame:

xyplot(PM10 ~ Ref | WR, data = dat, type = c('p', 'r'))

The plot looks silly with the data snippet you provided, but should
hopefully look more sensible with the complete data. The code creates
a four panel plot, one per direction, with points and a least squares
regression line fit in each panel. The regression line is specific to
a data subset, not the entire data frame.

HTH,
Dennis

On Sat, Aug 13, 2011 at 5:43 AM, maggy yan <kiotoqq at googlemail.com> wrote:
> dear R users,
> my data looks like this
>
>         PM10       Ref   UZ     JZ         WT   RH   FT   WR
> 1   10.973195  4.338874 nein Winter   Dienstag   ja nein West
> 2    6.381684  2.250446 nein Sommer    Sonntag nein   ja  Süd
> 3   62.586512 66.304869   ja Sommer    Sonntag nein nein  Ost
> 4    5.590101  8.526152   ja Sommer Donnerstag nein nein Nord
> 5   30.925054 16.073091 nein Winter    Sonntag nein nein  Ost
> 6   10.750567  2.285075 nein Winter   Mittwoch nein nein  Süd
> 7   39.118316 17.128691   ja Sommer    Sonntag nein nein  Ost
> 8    9.327564  7.038572   ja Sommer     Montag nein nein Nord
> 9   52.271744 15.021977 nein Winter     Montag nein nein  Ost
> 10  27.388416 22.449102   ja Sommer     Montag nein nein  Ost
>
> .
>
> .
>
> .
>
> .
>
> til 200
>
>
> I'm trying to make a linear regression between PM10 and Ref for each of the
> four WR, I've tried this:
> plot(Nord$PM10 ~ Nord$Ref, main="Nord", xlab="Ref", ylab="PM10")
> but it does not work, because "Nord cannot be found"
> what was wrong? how can I do it? please help me
>
>        [[alternative HTML version deleted]]
>
>
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