Data Intro (14) Flashcards
SPSS
Help us analyze data without the need of coding
What is the main purpose of data preparation in marketing research?
To validate, clean, and format data so it can be properly analyzed using statistical tools.
Why is SPSS preferred over Excel for data analysis in marketing research?
SPSS offers a user-friendly interface, handles large datasets more efficiently, is less prone to formula errors, and keeps a log of actions.
Why not use Excel ?
- Limited ability to handle large data
- Prone to erros in formula
- No running log of actions
Data Processing Stages
- Data Validation
- Data Preparation
- Data Analysis
What happen in Data Validation ?
Confirm data collection occur as planned
Check for erros/problems
If possible adress or repair collection error
Data Preparation
- Data Entry - Convert data to electronic form
- Data Coding - Group and assign codes to responses
- Data Cleaning - Sort out errors and inconsistencies, add new variables
Data Preparation - Data entry
1 row per participant
Variables as columns
Data Preparation - Data Coding
Give variables meaningfull names
Group and assign numeric codes to any question responses that are open ended
Example of coding scheme
Beauty on the inside = 1
Beauty is natural = 2
Beauty is an attitude = 3
Dummy Coding
Yes = 1
No = 0
Data Preparation - Data Cleaning
Chech for data entry errors or data entry inconcistencies
Data Cleaning Assumption
Never erase or remove data . just flag in a new variable column - Poor data or similarly
Missing Data
- Missing Completely at Random (MCAR)
- Missing At Random (MAR)
- Missing not at Random (MNAR)
What is MCAR (Missing Completely at Random)?
No pattern in what’s missing — it’s totally random.
Example: A random form was damaged.
What is MAR (Missing at Random)?
Missingness is related to other known data, not the missing value itself.
Example: People with less education skip income.
What is MNAR (Missing Not at Random)?
Missingness is caused by the value that’s missing.
Non-response error
Example: Low-income people don’t report income because it’s low.
Options to Dealing with Missing Data
- Litwise Deletion
2, Pairwise Deletioin
- Recover the Values
- Imputation
Litwise Deletion
Delete all data from any participant with missing values
Only analyse cases with available data on each variable
Pairwise deletion
Analyze all cases with variables present
Recover the values
Administrator Surveys can catch this during survey completion
Imputation
Replace Missing Values with substitute values.
Uses regression to predict
Deletion
Mean exclusion in analysis, not actual deletion
What are the three common strategies to handle missing data?
Listwise Deletion: Remove all data from a participant with any missing values.
Pairwise Deletion: Use available data for each analysis.
Imputation: Replace missing data with estimated values (mean, median, regression-based).