Everything (Semester 2) Flashcards
Data Preparation/Pre-processing
the act of cleaning and consolidating raw data prior to using it for analysis
Primary process of data preparation
to ensure that the raw data is ready for processing and analysis
Initial step of questionnaire checking
check all questionnaires for completeness and interviewing quality.
Editing
review of the questionnaires with the objective of increasing accuracy and precision.
Ways to edit
Returning to the field, assigning missing values, discarding unsatisfactory respondents
Coding
assigning a code, usually a number, to each possible
response to each question
Fixed field codes
the number of records for each respondent is the same and the same data appear in
the same column(s) for all respondents, are highly desirable.
Category codes should be
mutually exclusive and
collectively exhaustive.
Codebook
coding instructions and
the necessary information about variables in the
data set.
what does a codebook contain?
-column number
-record number
-variable number
-variable name
-question number
-instructions for coding
Transcribing
transferring the coded data
from the questionnaires directly into computers by keypunching or other means.
Consistency checks
identify data that are out of the range, logically inconsistent or have extreme values
Substitute a neutral value
A neutral value, typically the mean response to the variable, is substituted for the missing responses.
Substitute an Imputed Response
The respondents’ pattern of responses to other questions are used to impute or calculate a suitable response to the missing questions.
Casewise deletion
cases or respondents, with any missing responses are discarded from the analysis
