search for: diff12estimate

Displaying 2 results from an estimated 2 matches for "diff12estimate".

2007 Sep 25
2
Need help with function writing
...interval ################################################## trtvec=as.factor(trtvec) boxplot(split(yvec,trtvec)) title(header) ybar=tapply(yvec,trtvec,mean) varvec=tapply(yvec,trtvec,var) nvec=table(trtvec) error.df=nvec[1]+nvec[2]-2 pooled.var=((nvec[1]-1)*varvec[1]+(nvec[2]-1)*varvec[2])/error.df diff12estimate=ybar[1]-ybar[2] stderr=sqrt(pooled.var*((1/nvec[1])+(1/nvec[2]))) tratio=diff12estimate/stderr twosidedP=2*(1-pt(abs(tratio),error.df)) tcrit=qt(1-alpha/2,error.df) lower=diff12estimate-tcrit*stderr upper=diff12estimate+tcrit*stderr calpha=1-alpha out=data.frame(diff12estimate,stderr,tratio,twoside...
2007 Sep 24
1
hypothesis testing
...interval ################################################## trtvec=as.factor(trtvec) boxplot(split(yvec,trtvec)) title(header) ybar=tapply(yvec,trtvec,mean) varvec=tapply(yvec,trtvec,var) nvec=table(trtvec) error.df=nvec[1]+nvec[2]-2 pooled.var=((nvec[1]-1)*varvec[1]+(nvec[2]-1)*varvec[2])/error.df diff12estimate=ybar[1]-ybar[2] stderr=sqrt(pooled.var*((1/nvec[1])+(1/nvec[2]))) tratio=diff12estimate/stderr twosidedP=2*(1-pt(abs(tratio),error.df)) tcrit=qt(1-alpha/2,error.df) lower=diff12estimate-tcrit*stderr upper=diff12estimate+tcrit*stderr calpha=1-alpha out=data.frame(diff12estimate,stderr,tratio,twoside...