Psychology key science skills

Variables:

Independent

Dependent

Experimental

Controlled

Something that can be different. In Psych usually about people. 

Eg: age, income, eye colour, at different times or places,   

IV - deliberately manipulated or varied by the experimenter (What you change)

DV- what is being measured in the research

EG - The group exposed to the IV

CG - A group not exposed to the IV to determine the effect of the IV.

Hypotheses

A clear statement predicting how changes in the IV will affect the value of the DV. No operationalisation of variables in hypothesis. Should include population. 

PIDD - population, IV, DV, direction (eg. lower or higher, improved or worsened)

Extraneous variables

(EV) Any variable other than the IV that could lead to changes in the value of the DV.

Confounding variable: (CV) any variable other than the IV that has a systematic effect on the value of the DV. No valid conclusions can be drawn if CV is present.

Participant allocation

Basic experiments use an experimental group, who receive the treatment (change in IV) and a control group who do not, and who then form a basis for comparison. 

Participants need to be allocated to these groups.

Random allocation

All participants have an equal chance of being selected for the control or experimental group. This should mean in a large enough sample that participant characteristics are spread out evenly between the two groups.

Experimental Designs

• Between subjects (formerly known as  independent groups)

• Within groups  (formerly known as  repeated measures)

• Mixed design

Key features

• Individuals are divided into different groups and complete only one experimental condition.

• Experiment can be completed on one occasion, no order effects to be controlled

• Each participant is in both the experiment and control group

• Repeated measures (twice)

• Participant variables can be controlled, smaller number of people needed

• Combines features of within and between subject design

• Researcher can assess the potential differences between two or more separate groups of participants (between subjects) as well as change in the individual members of each group over time (within subjects)

Advantage of each experiemnta design

Each score is unique and comparable

May be less time-consuming than within-subjects design as different participants can complete the different conditions simultaneously and procedures do not need to be repeated

Results more precise

Limitation of experiemntal designs

Less control over participant variables Order effect, getting bored by second experiment, can guess what the experiment is about Can be more costly and time consuming to plan, conduct, and then analyse results.

Laboratory experiment vs field experiment

 Laboratory experiment- psychological experiment that is conducted within a laboratory setting

Field experiment- a psychological experiment that is conducted outside the laboratory in a ‘real-world’ setting

Correlation study

A  research method used to investigate the relationship between variables without any control over the setting in which the relationship occurs or any manipulation by the researcher

Positive correlation

Negative correlation

Zero correlation

When two variables change in the same direction

When two variables change in opposite directions — as one variable increases, the other variable tends to decrease (and vice versa)

No relationship between two variables

Strength of correlation coefficients

What would these coefficients indicate about the two variables.
Figure 1.30 page 51

+1.00 = Very strong

-1.00 = Very strong

0.00 = Zero or no correlation

Correlation vs causation

Correlations show the existence and extent of relationships between variables but they do not necessarily indicate that one variable causes the other

Advantage of correlation studies

Can study variables like age, gender and personality, which can’t be changed experimentally

Limitation of correlation studies

Can’t determine cause and effect relationships

Population

The group of people

who are the focus of

the study and from

which the sample is

drawn.

Sample

A subset of the

research population

who participate in a

study.

Conenience sampling

Occurs in the easiest

way possible.

Random sampling

Every member of the

population has an

equal chance of being

selected for the

sample.

stratified sampling

The population is

broken into

subgroups.

Participants are then

selected based on

proportionate

characteristics.

Advantagesof the three types of sampling

Very quick and easy

free from bias, quick and easy

More representative of the population

Limitations of the three types of sampling

Not representative of the population

May not be representative

Time consuming

Self Reports

A  participant’s answers to questions presented by the researcher.

Free response vs fixed response: )

 Free response- allow participants to answer entirely as they want to. 

Fixed response-  A question that presents a number of fixed alternative answers from which participants are required to choose

Interviews

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

Questionnaires

Data collection tool with a written set of questions or other prompts designed to collect self-report data

Focus groups

In psychological research, a small set of people who share characteristics and are selected to discuss a topic of which they have personal experience

Advantages of self reports

Useful techniques for collecting any type of data on how people think, feel and behave. In particular, they are especially useful for measuring behaviours or other characteristics that cannot easily be directly observed.

Limitation of self report

Participants can introduce bias into their self-reports

social desirability effect. Participants may intentionally give false or misleading answers to create a favourable impression of themselves

Observational Studies

Involves collection of data by carefully watching and recording behaviour as it occurs without any intervention or manipulation of the behaviour being observed

advantages and disadvanates

Watching and recording behaviour in real-life settings

Difficult to determine causes of behaviour

Case Studies

An intensive, in-depth investigation of some behaviour, event or problem of interest in a single individual, group, organisation or situation

advantages and disadvantages

Case studies can avoid artificiality of case studies

Case studies can avoid artificiality of case studies

Simulation Studies

Reproducing situations of research interest in a realistic way to investigate the behaviour and/or mental processes of individuals in that environment

Advantages and disadvantages

Simulation provides insight into potential circumstances and events

It can be time-consuming and expensive.

random errors and what it reduces

chances variation in the measurement process

reduces- precision of a measurement

validity and reliability of a measurement

Systematic errors and what it reduces

inbuilt fault with the measurement process

reduces- accuracy of a measurement

validity of a measurement

Extraneous

A variable other than the IV that may cause a change in the DV and therefore may affect the results

Confounding

Variable other than the independent variable that has affected the results (the dependent variable) and whose effect(s) cannot be separated from that of the independent variable, thereby providing an alternative explanation(s) for the results

5 types of extraneous variables

participant, situational, demand characteristics, experimenter effect and placebo effect

participant variables and how do control them

The personal characteristics that individual participants bring to an experiment and which could influence their responses 

Use random assignment to divide your sample into control and experimental groups.

situational variables

External factors (other than the IV) associated with the experimental setting that may influence participant responses and therefore the results.

standardize the experimental environment by keeping factors like temperature, noise level, lighting, and time of day consistent across all participants and conditions

demand characteristics

Cues in an experiment that may influence or bias a participant’s response, thereby distorting the results

Double-blind procedures, Standardised testing conditions and procedures, Single-blind procedures

experimenter effect

Any influence on the results produced by the person carrying out the research

Don’t interact with the participants,

placebo effect

When there is a change in a participant’s behaviour due to their belief that they are receiving some kind of experimental treatment and they respond in accordance with that belief, rather than to the effect of the IV.

Placebo

beneficence

The commitment to maximising benefits and minimising the risks and harms involved in taking a particular position or course of action.

integrity

The commitment to searching for knowledge and understanding, and the honest reporting of all sources of information and results, whether favourable or unfavourable, in ways that permit scrutiny and contribute to public knowledge and understanding

justice

The moral obligation to ensure that there is fair consideration of competing claims; that there is no unfair burden on a particular group from an action; and that there is fair distribution and access to the benefits of an action.

non maleficnence

Minimising and avoiding the causations of harm

Respect

Consideration of, and due regard to, the extent to which living things have an intrinsic value and/or instrumental value

confidentiality

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

Debriefing

ethical guideline requiring that at the end of the experiment, the participant leaves understanding the experimental aim, results and conclusions including wellbeing checks where appropriate

Informed consent procedures

Ethical guideline requiring that participants understand the nature and purpose of the experiment, including potential risks, before agreeing to participate

Use of deception

When a researcher deliberately conceals the true purpose of the experiment from participants by misleading or misinforming them

Voluntary participation

Ethical guideline requiring that no coercion or pressure is put on the participant to partake in an experiment, and they freely choose to be involved

Withdrawal rights

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. 

Primary vs Secondary

Primary- information collected directly by the researcher (or through others) for their own purpose; compare with secondary data

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

Quantitative vs Qualitative

Quantitative vs Qualitative

Quantitative- numerical information on the ‘quantity’ or amount of what is being studied Qualitative-  non-numerical information involving the ‘qualities’ or characteristics of a participant’s experience of what is being studied

Objective vs subjective

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

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

Reliability

The extent to which a measure produces results that are consistent, dependable and stable

Repeatability vs reproducibility

Repeatability- the degree to which a specific research investigation obtains similar results when it is conducted again under the same conditions on all occasions

Reproducibility-  how close the results are to each other when an investigation is replicated under changed condition

Validity

 how close the results are to each other when an investigation is replicated under changed condition

Internal vs external

Internal- the extent to which an investigation actually investigated what it set out to investigate and/or claims to have investigated

External- he extent to which the results obtained for a study can be applied beyond the sample that generated them, specifically to individuals in a different setting and