\title{studies on the relationship between class attendance and grades in college students}
\description{results from 68 studies on the relationship between class attendence and class performance and/or grade point average in college students.}
\bold{studyid}   \tab \code{numeric}   \tab study number \cr
\bold{source}    \tab \code{character} \tab study source (journal, dissertation, other) \cr
\bold{sampleid}  \tab \code{numeric}   \tab sample within study number \cr
\bold{criterion} \tab \code{character} \tab criterion variable (grade, gpa) \cr
\bold{class}     \tab \code{character} \tab class type (science, nonscience) \cr
\bold{ni}        \tab \code{numeric}   \tab sample size \cr
the 68 studies included in this dataset provide information about the relationship between class attendance of college students and their performance (i.e., grade) in the class and/or their overall grade point average. some studies included multiple samples and hence the dataset actually contains 97 correlation coefficients.
the dataset was obtained via personal communication. note that this dataset differs just slightly from the one used by credé et al. (2010).
credé, m., roch, s. g., & kieszczynka, u. m. (2010). class attendance in college: a meta-analytic review of the relationship of class attendance with grades and student characteristics. \emph{review of educational research}, \bold{80}(2), 272--295. \verb{https://doi.org/10.3102/0034654310362998}
dat <- escalc(measure="zcor", ri=ri, ni=ni, data=dat)
### meta-analysis for the relationship between attendance and grades
res <- rma(yi, vi, data=dat, subset=criterion=="grade")
### estimated average correlation with 95\% ci/pi
### examine if relationship between attendance and grades differs for nonscience/science classes
res <- rma(yi, vi, mods = ~ class, data=dat, subset=criterion=="grade")
### estimated average correlations for nonscience and science classes
### examine if relationship between attendance and grades has changed over time
res <- rma(yi, vi, mods = ~ year, data=dat, subset=criterion=="grade")
### meta-analysis for the relationship between attendance and gpa
res <- rma(yi, vi, data=dat, subset=criterion=="gpa")
### examine if relationship between attendance and gpa has changed over time
res <- rma(yi, vi, mods = ~ year, data=dat, subset=criterion=="gpa")
### use a multilevel model to examine the relationship between attendance and grades
res <- rma.mv(yi, vi, random = ~ 1 | studyid/sampleid, data=dat, subset=criterion=="grade")
### use a multilevel model to examine the relationship between attendance and gpa
res <- rma.mv(yi, vi, random = ~ 1 | studyid/sampleid, data=dat, subset=criterion=="gpa")
education, correlation coefficients, multilevel models