Research issues (control of variables) Flashcards
Example of extraneous variable
Age of pps, noise in the background, light, difficulty of …
Extraneous Variables
(EV)
Any variables other than the IV that may affect the DV if it is not controlled. They are nuisance variables that interfere with the experiment.
Participant and situational
Participant EV
To do with differences between the participants
e.g. age, gender, intelligence, hearing ability, visual ability
Situational EV
Features of the experimental situation
e.g. temp of the room, font words + size, noise, difficulty of word list
How to control these extraneous variables?
IQ - preliminary IQ test - randomly allocate to cond A/B
Age - select age group (assuming young=better memory)
Knowledge of vocab - preliminary questionnaire (1st/2nd language, edu lvl/qualifications)
Confounding variables
They replace the IV. Variables that interfere with the effect of the IV. Makes it hard to tell if any change in the DV happens because of the IV or the confounding variable.
Demand characteristics
Any cue from the researcher/research situation that may be interpreted by pps as revealing the purpose of an investigation. It can lead to a CHANGE in behavior (no longer natural).
Please you effect (demand characteristics)
Go along with what they want
Screw you effect (demand characteristics)
Goes against what they want
Investigator effects
Any unwanted influence of the investigator on the research outcome.
Factors include: unconscious behavior (smiling, body lang, meddling), way experiment is carried out (e.g. leading ques), way it is designed
Randomization
Making as many things as random as possible to reduce investigator effects -
Standardization
Giving all participants the exact same environment, information, + experience
e.g. standard instructions, same timings, materials should be presented in the same way
