Lecture 1 Part 2: Data Flashcards
Data
A value or set of values representing a specific concept(s)
Any type of info collected/measured during research//experimentation
Construct
Variables we can conceptualize but can’t measure directly eg. Feelings
How to operationalize constructs?
By using a variable that we CAN measure and that we believe reflects the construct we’re interested in eg. Intelligence with an IQ test
Instruments
Tool used to collect data eg. MRI machine, Questionnaire
2 Main characteristics of instruments
- Accuracy
- Precision
Accuracy
How close measurements are to the true value
Precision
How close the measurements are to eachother, and how consistent/repeatable the measurements are eg. 0.5 vs 0.5219838347837
Types of reliability for psychological tests (4 main ones)
- Test-retest reliability
- Alternate forms reliability
- Split half reliability
- Inter-rater reliability
Test-retest reliability
consistency among scores when the same person takes exactly the same test multiple times
Alternate forms reliability
consistency of scores on different versions of a test
Split half reliability
Consistency between score on one half of a test and score on the other half
Inter-rater reliability
Consistency between two different raters judgements of how someone scored on a test
Floor effect
Measurements consistently tend to be near the “floor”, which is the bottom of the scale, people tend to score near 0
Ceiling effect
measurements consistently tend to be near the “ceiling” which is the top of the scale, people tend to score near 100
Likert Scale
A type of rating scale used to measure people’s attitudes/opinions/behaviors, consistent in of a statement or question (Strongly Agree—>Strongly Disagree)
Why are floor effects and ceiling effects problematic?
NO VARIATION = NO ANALYSES
