Chapter 1: extra begrippen Flashcards
What are quantitative and qualitative methods?
Quantitative: when numbers are involved
Qualitative: when language is analysed
What is falsification?
Data that contradicts your hypothesis or theory
What are independent, dependent, predictor, and outcome variables?
Independent variable: a variable thought to be the cause of some effect, a variable that the experimenter has manipulated.
Dependent variable: a variable thought to be affected by changes in an independent variable, the outcome.
Predictor variable: a variable thought to predict an outcome variable, another term for independent variable.
Outcome variable: a variable thought to change as a function of changes in a predictor variable, another term for dependent variable.
What is criterion, concurrent, predictive, and content validity?
Criterion validity: whether you can establish that an instrument measures what it claims to measure through comparison to objective criteria
Concurrent validity: when data are recorded simultaneously using the new instrument and existing criteria
Predictive validity: when data from the new instrument are used to predict observations at a later point in time
Content validity: assesses the degree to which individual items represent the construct being measured, and cover the full range of the construct
What is test-retest reliability?
Test the same group of people twice
The easiest way to test reliability
What is correlational, cross-sectional and longitudinal research?
Correlational research: two or more variables are assessed without manipulation
Cross-sectional study: at a single point in time
Longitudinal study: over extended periods of time
1 doesnt tell you about the causal influence of variables.
What is the tertium quid?
When the relationship of 2 variables you’re researching might be influenced by a third variable
these factors are called confounding variables (confounds)
What is Between-groups/between-subjects/independent design and Within-subject/repeated-measures design?
Between-groups/between-subjects/independent design: testing different entities. Each different group of entities take part in each experimental condition
Within-subject/repeated-measures design: manipulate the independent variable using the same entity.
What is unsystematic and systematic variation?
Unsystematic variation is a variation in performance due to random factors. These factors exist between the experimental conditions.
Systematic variation is a variation in performance created by a specific experimental manipulation. In one condition its manipulated and not in the other.
What is the sum of squared errors (SS)?
When you square deviations in order to overcome the minus sign. Adding these up is the SS. You can use the SS as an indicator of the total dispersion or total deviance of scores from the mean.
What is Probability density function (PDF)?
Probability density functions (PDF) defines the probability function representing the density of a continuous random variable lying between a specific range of values. You can draw such a function by plotting the value of the variable (x) against the probability of it occurring (y). the resulting curve is the probability distribution.
