key scientific skills

Question 1

operationalising IV & DV

Answer 1

involves defining how they will be manipulated or measured in the experiment (or other investigation).
- e.g: to measure intelligence — a score on a standardised intelligence test

Question 2

random sampling

Answer 2

every member of the population has an equal chance of being selected for the sample
advantages:
* free from bias
* Quick and easy
disadvantages:
* may not be representative of the population

Question 3

stratified sampling

Answer 3

population is broken into subgroups then selects participants from each group in the same proportion they appear in the population.
* e.g: 60% boys 40% girls in a school - choosing 6 boys 4 girls for an experiment

advantages:
* more representative of the population

disadvantages :
* time consuming
* resource intrensive
* results in a non-representative sample

Question 4

convenience sampling

Answer 4

a sample is selected in the quickest and easiest way possible
advantages:
* time and cost effective and participants can be accessed relatively easily due to their availability
disadvantages
- not representative of the population.

Question 5

controlled experiment

Answer 5

an experimental investigation to test the relationship between an IV and a DV, whilst controlling all other variables.
- eg: to test whether talking on a hand-held mobile phone while driving (one variable) causes or influences a change in driver reaction time (another variable)

Question 6

controlled variable

Answer 6

considered to have an effect on the dependent variable in an experiment so it needs to be held constant (‘controlled’) to remove its potential effects.
- provides a baseline for comparison for the IV

Question 7

correlational studies

Answer 7

used to investigate the relationship that exists between variables without any control over the setting in which the relationship occurs or any manipulation by the researcher
- there are no IVs or DVs, or control groups
- advantage: can be conducted outside an artificial laboratory situation where the results may also be more realistic.
- disadvantage: do not permit the researcher to draw firm conclusions about cause-and-effect relationships

Question 8

self-report

Answer 8

a participant’s answers to questions presented by the researcher - relies on research participants’ accounts of their own experiences and behaviours.
- advantage: an efficient means of collecting data from a large number of people in a relatively short period of time
- disadvantage: social desirability effect (participants may intentionally give false or misleading answers to create a favourable impression of themselves.)

Question 9

free-response and fixed-response questions

Answer 9

• allow participants to answer entirely as they want to
• present a number of ‘fixed’ alternative answers from which participants are required to choose

Question 10

interview

Answer 10

involves questions that are asked by the researcher with the intention of prompting and obtaining specific information from an individual participant

Question 11

questionnaire

Answer 11

a written set of questions or other prompts designed to draw out self-report information from participants on a topic of research interest

Question 12

focus group

Answer 12

a small set of people who share characteristics and are selected to discuss a topic of which they have personal experience.
- a leader conducts the discussion and keeps it on target while also encouraging free-flowing, open-ended debate

Question 13

observational study

Answer 13

involves collection of data by carefully watching and recording behaviour as it occurs without any intervention or manipulation of the behaviour being observed
- advantage: researchers can watch and record spontaneous, everyday behaviour without the need for any manipulation or intervention.
- disadvantage: cannot be used to determine the cause of the behaviour of interest that is observed, because many factors may influence that behaviour and there is a lack of control of such variables.

Question 14

case study

Answer 14

an intensive, in-depth investigation of some behaviour, activity, event or problem of interest in a single individual, group, organisation or situation
- advantage: useful for tracking and describing experiences and change over time.
- disadvantage: cannot test or establish a cause–effect relationship

Question 15

simulation studies

Answer 15

involve reproducing situations of research interest in a realistic way to investigate the behaviour and/or mental processes of individuals in that environment
- advantage: can also be used when an investigation is not ethically permissible
- disadvantage: environments are artificial and therefore the studies may lack realism

Question 16

random errors

Answer 16

errors due to some chance factor or chance variation in a measurement

Question 17

systematic errors

Answer 17

produced by some factor that consistently favours one condition rather than another
- affects accuracy

Question 18

personal errors

Answer 18

a fault or mistake by the researcher

Question 19

extraneous variables

Answer 19

variables which are not controlled for and has an unwanted effect on the results.

Question 20

confounding variables

Answer 20

a variable other than the IV which has a systematic effect on the DV
- not controlled by the researcher

Question 21

accuracy

Answer 21

relates to how close it is to the true value of the quantity being measured. Accuracy is not quantifiable; measurement values may be described as being more accurate or less accurate.

Question 22

precision

Answer 22

refers to how closely a set of measurement values agree with each other

Question 23

repeatability

Answer 23

• the closeness of the agreement between the results of successive measurements of the same quantity being measured, carried out under the same conditions of measurement
• same researcher

Question 24

reproducibility

Answer 24

the closeness of the agreement between the results of measurements of the same quantity being measured, carried out under changed conditions of measurement.
- different researcher

Question 25

validity

Answer 25

• a measurement is said to be valid if it measures what it is supposed to be measuring
• an experiment is said to be valid if it investigates what it sets out and/or claims to investigate.

Question 26

types of validity

Answer 26

• internal validity refers to how successfully an experiment measures what it was intended to measure
• external validity refers to the extent to which research findings can be generalised to a greater population

Question 27

individual/participant differences.

Answer 27

• difference in participants which bias results.
• control with matched participants.

Question 28

placebo effect

Answer 28

experimental group administered treatment display physiological changes due to placebo and not due to treatment.
- control by giving control placebo (to raise baseline) or with single-blind in which participant does not know their group.

Question 29

order effects

Answer 29

• occurs in within-subjects; participant’s performance is impacted by participation in previous trials.
• control with counterbalancing (groups do conditions in different, balanced, orders).

Question 30

experimenter effects

Answer 30

• groups received varied treatment from experiments and bias results.
• control with standardized procedure between experimenters and/or double-blind in which neither experimenter nor participants know their group.

Question 31

demand characteristics

Answer 31

• individuals think they know the expected results of the study and consciously change behaviour accordingly.
• hawthorne effect: subjects change behaviour when knowing they’re being watched; typically in observational studies.
• control with single or double blind.

Question 32

unstandardised instructions/methods.

Answer 32

control with scripts, standardized procedures etc.

Question 33

between-subjects

Answer 33

comparing participants in two or more different conditions - independent groups
- advantage: cost and time efficient
- disadvantage: individual participant differences across groups

Question 34

within-subjects

Answer 34

an experimental design in which participants complete every experimental condition
- advantage: no participant differences, tracks individual change
- disadvantage: order effects—requires counterbalancing

Question 35

mixed design

Answer 35

has both between-subjects factors and within-subjects factors.
- advantage: uses fewer participants
- disadvantages: more complex design to execute

Question 36

primary data

Answer 36

info collected directly from the source by the researcher (or through others) for their own specific purpose.

Question 37

secondary data

Answer 37

information that was not collected directly by the current researcher but was collected at an earlier time by someone else.

Question 38

quantative data

Answer 38

information that is expressed numerically.

Question 39

qualitative data

Answer 39

information that is not expressed numerically - descriptive

Question 40

objective data

Answer 40

information that is observable, measurable, verifiable and free from the personal bias of the researcher.

Question 41

subjective data

Answer 41

information that is based on personal opinion, interpretation, point of view or judgment.

Question 42

confidentiality

Answer 42

the privacy, protection and security of a participant’s personal information in terms of personal details and the anonymity of individual results, including the removal of identifying elements.

Question 43

debriefing

Answer 43

ensures that, at the end of the experiment, the participant leaves understanding the experimental aim, results and conclusions. Any participant questions are addressed, and support is also provided to ensure there is no lasting harm from their involvement in the study. Debriefing is essential for all studies that involve deception.

Question 44

informed consent procedures

Answer 44

ensure participants understand the nature and purpose of the experiment, including potential risks (both physical and psychological), before agreeing to participate in the study. Voluntary written consent should be obtained by the experimenter and if participants are unable to give this consent, then a parent or legal guardian should provide this.

Question 45

use of deception in research

Answer 45

is only permissible when participants knowing the true purpose of the experiment may affect their behaviour while participating in the study, and the subsequent validity of the experiment. The use of deception is discouraged in psychological research and used only when necessary.

Question 46

voluntary participation

Answer 46

ensures that there is no coercion of or pressure put on the participant to partake in an experiment, and they freely choose to be involved.

Question 47

withdrawal rights

Answer 47

involves a participant being able to discontinue their involvement in an experiment at any time during or after the conclusion of an experiment, without penalty.
- may include the removal of the participant’s results from the study after the study has been completed.

Question 48

literature review

Answer 48

involves the collation and analysis of secondary data related to other people’s scientific findings and/or viewpoints in order to answer a question or provide background information to help explain observed events, or as preparation for an investigation to generate primary data

Question 49

classification and identification

Answer 49

classification: the arrangement of a phenomenon, objects or events into manageable sets
identification: a process of recognition of phenomena as belonging to particular sets or possibly being part of a new or unique set.

Question 50

modelling

Answer 50

involves construction and/or manipulation of either a physical model, such as a small- or large-scale representation of an object, or a conceptual model that represents a system involving concepts that help people know, understand or stimulate the system.

Question 51

product, process or system development

Answer 51

design or evaluation of an artefact, process or system to meet a human need, which may involve technological applications in addition to scientific knowledge and procedures.