[R] lm for log log

2010-06-20 Thread Ekaterina Pek
Hi, It's rather statistical question than R-question. There is some linear correlation but the picture plot(a,b) + abline(lm(b~a)) is quite crowded in the left lower corner. The picture plot(log(a), log(b)) + abline(lm(log(b)~log(a)) is much nicer (Milky Way). Is it correct to use the second

Re: [R] lm for log log

2010-06-20 Thread Ted Harding
On 20-Jun-10 12:02:58, Ekaterina Pek wrote: Hi, It's rather statistical question than R-question. There is some linear correlation but the picture plot(a,b) + abline(lm(b~a)) is quite crowded in the left lower corner. The picture plot(log(a), log(b)) + abline(lm(log(b)~log(a)) is much

Re: [R] lm for log log

2010-06-20 Thread Ekaterina Pek
Hi, Ted. Thanks for your reply. It helped. I have further a bit of questions. It may be that lm(log(b) ~ log(a)) is, from a substantive point of view, a more appropriate model for whetever it is than lm(b ~ a). Or it may not be. This is a separate question. Again, Spearman's rho is not

Re: [R] lm for log log

2010-06-20 Thread David Winsemius
On Jun 20, 2010, at 1:38 PM, Ekaterina Pek wrote: Hi, Ted. Thanks for your reply. It helped. I have further a bit of questions. It may be that lm(log(b) ~ log(a)) is, from a substantive point of view, a more appropriate model for whetever it is than lm(b ~ a). Or it may not be. This is a

Re: [R] lm for log log

2010-06-20 Thread Ted Harding
On 20-Jun-10 19:54:02, David Winsemius wrote: On Jun 20, 2010, at 1:38 PM, Ekaterina Pek wrote: Hi, Ted. Thanks for your reply. It helped. I have further a bit of questions. It may be that lm(log(b) ~ log(a)) is, from a substantive point of view, a more appropriate model for whetever it is

Re: [R] lm for log log

2010-06-20 Thread David Winsemius
On Jun 20, 2010, at 8:17 PM, (Ted Harding) wrote: On 20-Jun-10 19:54:02, David Winsemius wrote: On Jun 20, 2010, at 1:38 PM, Ekaterina Pek wrote: Hi, Ted. Thanks for your reply. It helped. I have further a bit of questions. It may be that lm(log(b) ~ log(a)) is, from a substantive point of

Re: [R] lm for log log

2010-06-20 Thread David Winsemius
On Jun 20, 2010, at 9:14 PM, David Winsemius wrote: On Jun 20, 2010, at 8:17 PM, (Ted Harding) wrote: On 20-Jun-10 19:54:02, David Winsemius wrote: On Jun 20, 2010, at 1:38 PM, Ekaterina Pek wrote: Hi, Ted. Thanks for your reply. It helped. I have further a bit of questions. It may

Re: [R] lm for log log

2010-06-20 Thread Ted Harding
On 21-Jun-10 01:30:26, David Winsemius wrote: On Jun 20, 2010, at 9:14 PM, David Winsemius wrote: On Jun 20, 2010, at 8:17 PM, (Ted Harding) wrote: On 20-Jun-10 19:54:02, David Winsemius wrote: On Jun 20, 2010, at 1:38 PM, Ekaterina Pek wrote: Hi, Ted. Thanks for your reply. It helped. I