For the t-test, you used the two-tailed t-test. It is the default. Here I think you should set alternative="less" in the t.test function.
2014-06-29 8:41 GMT-05:00 dhs <bravo0...@me.com>: > Trying to understand how to analyze my data, sample data follows. I want > to know if the student scores increased from sem1 to sem2 (semesters), and > whether the inGroup scores increase more. > Hereâs what I did with sample data: > > students <- c("s1â, âs2â, "s3") > inGroup <- c(T, F, T) > score <- c(4, 3, 4, 6, 4, 6) > time <- as.factor(c("sem1","sem1","sem1", "sem2","sem2","sem2")) > > data <- data.frame(students, inGroup, score, time) > > #to determine if scores for all students increased over time I did a t.test > t.test(data[data$time=="sem1","score"],data[data$time=="sem2","score"], > paired=T) > > #to determine if the inGroup had a greater increase I did a mixed effect > anova > library("lme4") > mixedEffect <- lme(score~time, data=data,random=~ 1 | inGroup, na.action > = na.exclude); summary(mixedEffect) > > > Is this right? in the above the t-Test p-value <.05 so there was a > significant change. the mean of differences was -1.66 so the change was an > increase? > > For the mixed effect the difference was significant, p < 0.5 timesem2 is > this right? If so how do I know if the inGroup scores increased more? > [[alternative HTML version deleted]] > > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > > [[alternative HTML version deleted]]
______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.