Problems with lm()
In your data, subject is nested within sequence. Was that your intention?
a<-c(1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14) b<-c(1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2) c<-c(2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2) d<-c(2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1) e<-c(1739,1633,1481,1837,1780,2073,1374,1629,1555,1385,1756,1522,1566,1643,
+ 1939,1615,1475,1759,1388,1483,1127,1682,1542,1247,1235,1605,1598,1718 + )
Data<-data.frame(subject=as.factor(a),
+ drug=as.factor(b), period=as.factor(c), + sequence=as.factor(d), Max=e)
Data
subject drug period sequence Max 1 1 1 2 2 1739 2 1 2 1 2 1633 3 2 1 1 1 1481 4 2 2 2 1 1837 5 3 1 2 2 1780 6 3 2 1 2 2073 7 4 1 1 1 1374 8 4 2 2 1 1629 9 5 1 2 2 1555 10 5 2 1 2 1385 11 6 1 1 1 1756 12 6 2 2 1 1522 13 7 1 2 2 1566 14 7 2 1 2 1643 15 8 1 1 1 1939 16 8 2 2 1 1615 17 9 1 2 2 1475 18 9 2 1 2 1759 19 10 1 1 1 1388 20 10 2 2 1 1483 21 11 1 2 2 1127 22 11 2 1 2 1682 23 12 1 1 1 1542 24 12 2 2 1 1247 25 13 1 2 2 1235 26 13 2 1 2 1605 27 14 1 1 1 1598 28 14 2 2 1 1718 Andrew
On Thu, Jun 19, 2008 at 04:29:16PM +0800, leeznar wrote:
Dear R-users: I am a new R-user and I have a question about lm function. Here is my data. a<-c(1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14) b<-c(1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2) c<-c(2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2) d<-c(2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1) e<-c(1739,1633,1481,1837,1780,2073,1374,1629,1555,1385,1756,1522,1566,1643,1939,1615,1475,1759,1388,1483,1127,1682,1542,1247,1235,1605,1598,1718 ) Data<-data.frame(subject=as.factor(a), drug=as.factor(b), period=as.factor(c), sequence=as.factor(d), Max=e) lm3<- lm(Max ~subject*sequence + sequence + period + drug, data=Data) print(lm3) anova(lm3) When I use lm to fit the data, there are some problems in ??subject*sequence??. I have use GLM in SPSS to fit the same data, and it seems there is no problem. I don??t know where my problem is. How can I get the same result with SPSS? How can I do? Best regards, Hsin-Ya Lee
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