In recent years, funding agencies like the Institute of Educational
Sciences and the National Science Foundation have increasingly
emphasized large-scale studies with experimental and quasi-experimental
designs looking for 'objective truths'. Educational researchers have
recently begun to use large-scale studies to understand what really
works, from developing interventions, to validation studies of the
intervention, and then to efficacy studies and the final "scale-up" for
large implementation of an intervention. Moreover, modeling student
learning developmentally, taking into account cohort factors, issues of
socioeconomics, local political context and the presence or absence of
interventions requires the use of large data sets, wherein these
variables can be sampled adequately and inferences made. Inroads in
quantitative methods have been made in the psychometric and sociometric
literatures, but these methods are not yet common knowledge in the
mathematics education community. In fact, currently there is no volume
devoted to discussion of issues related to large-scale studies and to
report findings from them. This volume is unique as it directly
discusses methodological issue in large-scale studies and reports
empirical data from large-scale studies.