You can seek help from Consulting for Statistics, Computing and Analytics Research (CSCAR)

FAQ

• Longitudinal study / mixed effects modeling / correlated error / repeated measurements in R: lme4::lmer, lme4::glmer, lmerTest::.

• Multiple tests / post-hoc tests in R / Tukey's test in ANOVA, ANCOVA): stats::TukeyHSD, multcomp::glht.

• Post-hoc test in mixed-effects models: lsmeans:lsmeans.

• Change reference category of a factor in R: stats::relevel

Miscellaneous

Some small side projects from clients

• Automating nurse workload balancing at U of Michigan Hospital. For 3 shifts a day nurses will be assigned patients to care for; each patient carries an expected workload calculated by his conditions and treatment. Nurses working the same shift (except those who straddle two hospital wings, and/or work multiple shifts) are expected to have similar workload. See example data files (work schedule, nurse info) and R-script.

• Sending POST reqests, parsing JSON responses, and formating data (from the LobbyView database) using R (script), and Python (script).

• A small tool for finding most time-slots coverage using gathered responses from Google Forms, since Google Forms does not provide this function. See example data file and script

Bugs

• If you ever see an error like the following when installing a package in R, it's because the list of packages on the RStudio mirror is not well-maintained. A newer version is available for download but the list is apparantly outdated. Just use another mirror.

trying URL 'https://cran.rstudio.com/src/contrib/pillar_1.1.0.tar.gz'
Warning in install.packages :
  cannot open URL 'https://cran.rstudio.com/src/contrib/pillar_1.1.0.tar.gz':
 HTTP status was '404 Not Found'