DATA PREPARATION AND ANALYSIS OF DATA
Data Preparation
Logging The Data
Checking The Data For Accuracy
Developing A Database Structure
Set up a procedure for logging the information and keeping track until of it until you are ready to do a comprehensive data analysis
The data analyst should always be able to trace a result from a data analysis back to the original forms on which the data is collected
As soon as data is received you should screen it for accuracy
Are the responses legible/readable?, Are all important question answered?
The database structure is the manner in which you intend to store the data for the study so that it can be accessed in subsequent data analyses
Two option for storing data in computer - database programs and statistical programs
Entering The Data Into The Computer
To assure a high level of data accuracy, the analyst should use a procedure called double entry
In this procedure you enter the data once. Then, use a special program that allows you to enter the data a second time and checks each second entry against the firsy
Data Transformation
Once the data have been entered it is almost always necessary to transform the raw data into variables that are useable in the analyses
Missing values, Item reversals, Scale totals,and categories
The Process of Data Analysis
1) Data Cleaning
2) Initial Data Analysis
3) Main Data Analysis
Data are inspected, and erroneous data are - if necessary, preferable, and possibly corrected
Data cleaning can be done during the stage of data entry
During initial data analysis one refrains from any analysis that are aimed at answering the original research question
Quality of Data
Quality of Measurement
Should only be checked during the initial data analysis phase when this is not the focus or research question of the study
Confirmatory factor analysis and analysis of hemogeneity
Characteristics of Data Sample
Should be checked as early as possible
Different types of analyses: frequency counts, descriptive statistics, normality.
Basic statistics of important variables
Scatter plots
Correlations
Cross-tabulations
Aimed at answering the research question are performed as well as any other relevant analysis needed to write the first draft of the research report
Usually the approach is decided before data is collected