experimental method

Question 1

experimental method

Answer 1

involves the manipulation of an IV to measure the effect on the DV. experiments may be laboratory, field, natural or quasi

Question 2

aims

Answer 2

a general statement of what the researcher intends to investigate, the purpose of the study

• when the focus of the research has been narrowed down
• developed from theories
• general statements to describe the purpose of the investigation

Question 3

variable

Answer 3

a variable is anything that is open to change

Question 4

Independent variable

Answer 4

this is something that the researcher changes or manipulates

Question 5

dependent variable

Answer 5

this is something that the researcher measures, to see if there has been change

Question 6

operationalising variables

Answer 6

clearly defining variables in terms of how they are measured

Question 7

hypothesis

Answer 7

this is a clear, precise, testable statement that predicts the outcome of a study

Question 8

experimental hypothesis

Answer 8

this states that there is a significant difference between variables

Question 9

directional hypothesis

Answer 9

this states that there is a significant difference between variables

Question 10

non-directional hypothesis

Answer 10

this does not state the direction of the difference, psychologists use non-directional hypothesis when there is no previous research, or no findings from previous research are contradictory

Question 11

null hypothesis

Answer 11

this states that there is no significant difference between variables

Question 12

extraneous variable

Answer 12

this is any variable other than the IV that may have an effect on the DV if it is not controlled. This could include any change in environmental conditions, such as background noise or time of day

Question 13

confounding variable

Answer 13

variables which systematically affect the dv, this can distort the role of the iv

Question 14

demand characteristics

Answer 14

any cue from the researcher or from the research situation that may be interpreted by participants as revealing the purpose/aim of the investigation; this may lead a participant to change their behaviour within the research situation. they may act in way that is expected and over-perform to please the experiment or they may deliberately underperform to sabotage the results of the study. either way participant’s behaviour is not natural

Question 15

investigator effect

Answer 15

this is when the person collecting the data has knowledge of what the research aim is and that knowledge affects the data obtained (consciously and unconsciously). this may include the design of the study, the selection of participants or interaction with participants during the research process

Question 16

standardisation

Answer 16

all participants should be subject to the same environment, information and experience. to ensure this, all procedures are standardised, so there is a list of exactly what will be done in the study. this also includes standardised instructions that are read to each participant. standardisation is an attempt to control for investigator effects as the researcher’s interaction with participants during the research process is controlled

Question 17

randomisation

Answer 17

this refers to the use of change to make key decisions about how the experiment is conducted. random number generators, throwing a dice, flipping a coin. This is an attempt to control for investigator effects as this reduces the researcher’s influence of the design of an investigation

Question 18

reliability

Answer 18

refers to how consistent the findings from an investigation or measuring device are. if a measurement/finding is repeated, then it is described as reliable

Question 19

test-retest reliability

Answer 19

is a way of assessing the reliability of a questionnaire of psychological test, it can also be applied to intervews

Question 20

inter-observer reliability

Answer 20

inter-observer reliability is a method of assessing the reliability of observations

Question 21

validity

Answer 21

refers to whether a psychological test, observation or experiment produces a result that is genuine

Question 22

internal validity

Answer 22

the extent to which the researcher is measuring what they intended to, so the effects observed in an experiment are due to the manipulation of the IV and not confounding variables

Question 23

external validity

Answer 23

the extent to which the findings can be generalised beyond the research situation in which they were found

Question 24

ecological validity

Answer 24

this is the extent to which the findings from a research study can be generalised to other settings and situation

Question 25

temporal validity

Answer 25

the extent to which findings from a research study can be generalised to other historical times and eras

Question 26

population validity

Answer 26

the extent to which findings from a sample can be generalised to the target population