Forwarded message: > From: "Byungchul Cha" <[email protected]> > We use "Intro to the practice of statistics" by Moore, McCabe, Craig as textbook. Is there an option for the command "t.test" so that it can perform t-test from the summary of sample data (that is, sample mean, sample sd, and sample size), instead of the (raw) sample data? I've been looking to find a way to do so, but, I couldn't. I believe it is possible to write codes to do this for my own use, but, I am just curious. Is there a pedagogical reason not to do so?
YES! One of the reasons to use statistical software in a first course is so that students can work with real, raw data. For example, it is nearly imnpossible to check assumptions if you do not have the data. However, publishers want to sell books to EVERYONE, including those who do not have or do not use any technology beyond a $2 calculator. So the homework problems are driven by this least common denominator. These data-free homework problems provide practice in plugging numbers into formulae, an Algebra I or even junior high school skill, and a pretty minor skill for doing statistics in the real world. So I would suggest not assigning these and replacing them with problems that involve real data, and asking students to LOOK AT THE DATA to check assumptions and look for gross errors. I think you can find many real data sets on the CD that comes with this text, and many are included with R as well. Other sources include DASL and the _Journal of Statitics Education_. -------> First-time AP Stats. teacher? Help is on the way! See http://courses.ncssm.edu/math/Stat_Inst/Stats2007/Bob%20Hayden/Relief.html Robert W. Hayden, P.O Box 450, North Troy, VT 05859 phone (802) 988-2587 web site http://statland.org/ email bob statland.org (add your own "@" and save me some spam) _______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-sig-teaching
