Research methods - Types of Experiment

Question 1

what is a lab experiment

Answer 1

an experiment that is conducted in a highly controlled, artificial environment. by creating the experiment artificially, the experimenter can control many variables, e.g by using standardised instructions to ensure each participant is treated in the same way

Question 2

why may a researcher choose to conduct a lab experiment

Answer 2

control of extraneous variables means we can be confident that it is the manipulation of the IV that has caused the change in the DV

Question 3

define internal validity

Answer 3

the extent to which a study is measuring what it set out to measure

Question 4

what is external validity

Answer 4

the extent to which the results from the experiment can be generalised beyond the particular study to other people and settings

Question 5

give four factors that could affect the internal validity of a study

Answer 5

demand characteristics, extraneous variables, researcher bias, researcher effects

Question 6

define demand characteristics

Answer 6

cues in an experimental situation that communicate to participants what is expected of them, which can then lead to participants changing their behaviour to help or hinder the research

Question 7

define extraneous variables

Answer 7

any variable other than the IV that could have an impact of the DV

Question 8

define researcher bias

Answer 8

a researcher’s expectations or beliefs influence the design of the research or the collection of data

Question 9

define researcher effects

Answer 9

anything that the researcher does that has an effect on the participant’s performance in a study - can be direct or indirect e.g way the study is designed

Question 10

what are the two types of external validity

Answer 10

ecological validity and population validity

Question 11

define ecological validity

Answer 11

the ability to generalise a research effect beyond the particular setting in which it is demonstrated to other settings

Question 12

define mundane realism

Answer 12

the degree to which the task being completed is similar to events which occur in the real world

Question 13

define population validity

Answer 13

the extent to which the results of a study can be generalised to other groups of people besides those who took part in the study

Question 14

when would a study lack population validity

Answer 14

if the sample is not representative

Question 15

what is reliability

Answer 15

a measure of consistency both within a study (internal reliability) and also over time such that is is possible to obtain the same results on subsequent occasions when exactly the same procedure is used (external reliability)

Question 16

what does the standardisation of lab experiments allow

Answer 16

researchers can compare the results and test for internal reliability, as well as allowing for other researchers to replicate the study again in the future and test for external reliability

Question 17

what are the strengths of lab experiments

Answer 17

high level of control over extraneous variables - increased internal validity and cause and effect can be established

standardised procedures which means that every participant will have the same experience (internal reliability) and allows for replication in the future (external reliability)

Question 18

what are the weaknesses of lab experiments

Answer 18

due to being conducted in artificial settings, participants may not behave naturally - low ecological validity

participants are more likely to guess the aim of the study due to artificial settings and change their behaviour - decreases internal validity

risk of researcher bias as their expectations/beliefs may affect how they interact with participants or alter their interpretation of results

Question 19

what is a field experiment

Answer 19

there is an IV that is manipulated by the researcher and a DV that is measured but the setting is the participant’s normal environment in relation to the behaviour being studied

Question 20

what are the strengths of field experiments

Answer 20

behaviour is investigated in settings in which it would usually occur which means it is more likely to reflect real life - high ecological validity

ps are less likely to show demand characteristics as they often (but not always) don’t know they are being studied - increases internal validity

Question 21

what are the weaknesses of field experiments

Answer 21

due to behaviour being investigated in natural settings, researcher has less control over extraneous variables - lower internal validity

ps are often unaware that they are being studied in a field experiment so ethical issues - lack of informed consent

replication may prove difficult as the naturalistic setting may be hard to repeat exactly - external reliability may be decreased

Question 22

what are quasi experiments

Answer 22

where the IV is naturally occurring and cannot be manipulated by the experimenter - the IV is a difference between people that already exists ie gender and the researcher examines the effect this has on the DV

Question 23

where can be quasi experiments be conducted

Answer 23

lab or field settings

Question 24

why might it be useful to use a quasi experiment

Answer 24

allows research where an IV can’t be manipulated due to ethical or practical reasons

Question 25

what are the issues of using quasi experiments

Answer 25

ps cannot be randomly allocated due to the conditions of the IV meaning there is less control over ps variables

may not be replicable as naturally occurring IV may be rare - lowers external reliability