1 - the experimental method Flashcards
define aim
a general statement made by the researcher which tells us what they plan on investigating (purpose of study). developed from theories and similar research.
define hypothesis
statement that clearly states the relationship between the variables being investigated
what is the difference between a directional and non directional hypothesis
directional states direction the the relationship that will be shown between variables whereas non directional does not
when is a directional hypothesis used
when there is already research which relates to the aim of the researcher’s investigation, suggesting a particular outcome
when would a non directional hypothesis be appropriate
when there is no previous research which relates to the aim or the research is contradictory
in order to test the effect of the iv we need what two conditions!
experimental condition and control conditoon
define operationalisation of variables
researcher clearly defining the variables in terms of how they are being measured
define extraneous variable
any other variable which is not the iv that affects the dv and does not vary systematically with the iv (do not confound results just make them harder to detect)
define confounding variable
like extraneous variable but changes systematically with the iv. becomes difficult for researcher to be sure of the origin of the impact of the dv as the confounding variable could have been the cause
define demand characteristics
any cue the researcher may give which makes the participant feel like they can guess the aim of the investigation
what can demand characteristics look like?
acting in a way they think the researcher wants them to or intentionally underperforming to sabotage the results
define investigator effects
any unwanted influence from the researchers behaviour on the dv measured
define randomisation
use of chance to reduce the effects of bias from investigator effects
define standardisation
using the exact same formalised procedures and instruction for every participant
what can randomisation and standardisation minimise the effects of?
extraneous or confounding variables
what are the four types of experiments?
laboratory, field, quasi and natural
define a laboratory experiment
takes place in an environment where different variables can be carefully controlled
define a field experiment
natural environment but with variables still being well controlled
define a quasi experiment
the iv has not been determined by the researcher, instead it naturally exists
define natural experiment
iv not brought about by researcher, would have happened anyways
how is high level of control a strength of lab studies
iv has been precisely replicated, leading to greater accuracy
how is replication a strength of lab studies
researchers can repeat experiments and check results
how is experimenter’s bias a weakness of lab studies
bias can affect results and ps may be influenced by these expectations
how is low ecological validity a weakness of lab studies
high degree of control makes the situation artificial
how is naturalistic a strength of field studies
more natural behaviours hence high ecological validity even if iv is still controlled
how is ethical considerations a weakness of field studies
invasion of privacy and likely to have been no informed consent
how is loss of control a weakness of field studies
loss of control over extraneous variables hence precise replication not possible
how is controlled conditions a strength of quasi experiments
hence replicable, likely to have high internal validity
how is not being able to randomly allocate participants a weakness of quasi experiments
cannot randomly allocate ps to conditions so may be confounding variables presented. harder to conclude that iv caused the dv
how is providing opportunities for research a strength of natural studies
research may have been otherwise impossible due to practical or ethical reasons
how is high external validity a strength of natural studies
dealing with real life issues
how is natural occurring event being rare a weakness of natural studies
means these experiments are not likely to be replicable hence hard to generalise findings
how is difficulty to randomise groups a weakness of natural studies
confounding and extraneous variables become a problem
