R help - Feb 2016 - Help for survival curves for the survfit object‏

Hi guy,I have some problems when plotting survival curves for the survfit
object.My survfit model is as
follows:fit6<-survfit(Surv(Survival_time_year_,event)~Race_1_Desc,data=data6)Race_1_Desc
is a indicator variable which has 0 and 1 values.However, in my dataset, all of
the Race_1_Desc are of value 0, which means I have only 1 group.When I plot my
survival curve use the following
command,plot(fit6,col=c("blue","red"),xlab="Survival
Time",ylab="Survival Probability",main="Survival Plot for
Leaf 6")  It is correct that I only has one curve for Race_1_Desc coded as
0, which is the blue full line. But there are also two dashed line, one is red
and one is blue.I just want to know what are the two dashed lines mean and why
the show up in the plot.
 		 	   		  
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On 2016-02-08 14:11, ??? wrote:
> Hi guy,I have some problems when plotting survival curves for the
> survfit object.My survfit model is as
>
follows:fit6<-survfit(Surv(Survival_time_year_,event)~Race_1_Desc,data=data6)Race_1_Desc
> is a indicator variable which has 0 and 1 values.However, in my
> dataset, all of the Race_1_Desc are of value 0, which means I have
> only 1 group.When I plot my survival curve use the following
>
command,plot(fit6,col=c("blue","red"),xlab="Survival
> Time",ylab="Survival Probability",main="Survival Plot
for Leaf 6")
> It is correct that I only has one curve for Race_1_Desc coded as 0,
> which is the blue full line. But there are also two dashed line, one
> is red and one is blue.I just want to know what are the two dashed
> lines mean and why the show up in the plot.
Maybe they are confidence limits? Read the help page for plot.survfit, 
especially 'conf.int'.

G?ran

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> version deleted]]
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