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Preface
A common statistical programmer’s task generally begins with reading
one or more raw data sets into a statistical software and performing data
management and manipulation, such as checking and modifying values of
variables to ensure they satisfy the analytic quality, transposing data into
a desired shape for a certain type of statistical analysis, merging multiple
data sets by common variables, etc. Once the data has been assured of pos-
sessing the desired quality, the transformed data is ready for statistical
analysis by using procedures that are provided by the statistical software.
Data manipulation is an essential step to obta ...