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Chapter 15 Data Preparation & Analysis of Data - Coggle Diagram
Chapter 15 Data Preparation & Analysis of Data
Data preparation is a process of inspecting, cleaning, transforming and modelling data with the goal of highlighting useful information, suggesting conclusions & supporting decision making.
Data Preparation
Developing database structure
To store the data for the study so that it can be accessed in subsequent data analyses
Two options for storing data on computer - database programs & Statistical programs.
Entering data into the computer
To assure a high level of data accuracy, the analyst should use a procedure called double entry
However, these double entry programs are not widely available & require some training.
Checking the data for accuracy
As soon as data is received you should screen it for accuracy
Doing this right away will allow you to go back to the sample to clarify any problems / error
Data transformation
Once the data have been entered it is almost always necessary to transform a raw data into variables that are usable in the analyses
Missing values - Many analysis program automatically treat blank values as missing values
Lodging the data
Set up a procedure for logging the information & keeping track of it until you are ready to do a comprehensive data analysis
Different researcher differ in how they prefer to keep track of incoming data
The process of data analysis
Initial data analysis
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
Characteristic of data sample - Basic statistics of important variables, Scatter plots, Correlations & Cross-tabulations
Quality of data - should be checked as early as possible. Other initial data quality checks are checks on data cleaning, analysis of missing observation, analysis of extreme observation, comparison & correction of differences in coding schemes
Main data analysis
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.
Data cleaning
An important procedure during which the data are inspected, & erroneous data are - if necessary, preferable and possibly corrected
Data cleaning can be done during the stage of data entry
Data analysis should be conducted in a standard way, using the guidelines given as the best practice. The data analysis process ranges from creating the database to producing the final results for the report.
The purpose of data preparation and data analysis is to obtain meaning from the collected data.