Correlation Quote by Howard Wainer
““It also makes clear why an observational study needs to collect lots of ancillary information about each participant so that the kind of balancing required can be attempted. In a true experiment, with random assignment, such information is (in theory) not required. Here enters Paul Holland, whose observations about the inevitability of missing data will further illuminate our journey.””
About This Quote
Source Book: Statistical Methods in Education and Psychology, Howard Wainer, 1999
Observational studies must gather extensive participant data to enable balancing, unlike randomized experiments that theoretically need none.
In simple terms: Collect lots of data in observations to balance groups; experiments need less.
Key Takeaway
Gather comprehensive data when randomization isn’t possible.
Themes
research design
data collection
bias control
Mood
analytical
cautious
Type
methodological
educational
When to use this quote
- clinical trials
- survey research
- epidemiology
- policy evaluation
Key Concepts
observational study
randomization
missing data
Questions to Reflect On
- How can you assess residual bias after balancing?
- What data are essential for your study?
A Different Perspective
Balancing may still be imperfect despite extensive data.
![“In the real world of research, conventional tests of [statistical] significance seem almost worthless.” quote by Fischer Black](https://sms4smile.com/quotes/img-quotes/3a4/fischer-black-60662_conventional_in-the-real-world-of-research-convention_163947.jpg)
