Methodology

• The aim is to find out if there are any differences between the two groups.
• A hypothesis is an educated guess about what might happen or be true, based on previous research or theory.
• An independent variable is the factor that changes across different conditions in an experiment.
• A dependent variable is the factor being measured (e.g., reaction time)
• Reliability:

  • the extent to which an assessment tool can produce results consistently, each time it is used
• Test re-test reliability

  • A measure of reliability obtained by administering the same test twice over some time to a group of individuals
• Parallel-forms reliability

  • A measure of reliability obtained by administering different versions of an assessment tool to the same group of individuals
• Split-half reliability

  • Determined by dividing the total set of items related to a construct of interest into halves and comparing the results obtained from the 2 subsets of items thus created
  • Involves dividing the original test into 2 halves and examining the correlation between them
• Inter-Rater Reliability

  • A measure of consistency used to evaluate the extent to which different judges agree in their assessment decisions
  • Used when data is collected by researchers assigning ratings scores or categories to one or more variables and it can help mitigate observer bias
• Validity

  • Refers to the extent to which an assessment tool actually measures what it is designed to measure
  • e.g. Research claims to measure intelligence it is only valid if it actually measures intelligence and not, for example, memory.
• Content Validity

  • Evaluates how well an instrument covers all relevant parts of the construct it aims to measure
  • Construct⇒ a theoretical concept, theme, or idea based on empirical evidence, it's a variable that's usually not directly measurable, such as time.
  • Essentially, do your questions in a test actually asses what you are wanting to measure.
• Criterion-related validity

  • Evaluates how accurately a test measures the outcome it was designed to measure.
  • Shows how well a test correlates with an established standard of comparison call a criterion
  • e.g. wace exam and score scaling
• Construct Validity

  • the extent to which your test or measure accurately asses what it's supposed to do
• Internal validity

  • The degree of confidence that the casual relationship you are testing is not influenced by other factors or variables
  • Essentially, while conducting the experiment, try to ensure nothing changes with the method/procedure or participants
• External Validity

  • Asks whether the findings of a study can be generalised to patients with characteristics that are different from those in the study
  • Can we generalise a study's findings to the wider population?
• Correlation

  positive correlation

  • relationship between 2 variables in which both variables move in the same direction
• negative correlation

  • relationship where 2 variables increase in one variable is associated with a decrease in the other
• zero correlation

  • exists when there is no relationship between 2 variables
• Prediction

  • if there is a relationship between 2 variables we can make predictions about one from another
• Validity

  • Concurrent validity (correlation between a new measure and an established measure)
• Reliability

  • test-retest reliability (are the measures consistent?)
  • inter-rater reliability (are observers consistent?)
• correlation coefficients

  • when studying things that are difficult to measure, we expect the correlation coefficients to be lower. when we are studying things that are easy to measure, such as economic status, we expect higher correlations
• Correlation v Causation

  • causation means that one variable causes the other variable
  • isolating and manipulating the independent variable to observe its effect on the dependent variable and control the environment in order for the extraneous variables
  • a correlation between variables, however does not automatically mean that the change in one variable is the cause of the change in the value of the other variable. A correlation only shows if there is a relationship between variables.
  • Correlation does not always cause causation, a third variable may be involved
• Observational study

  • An individual observing another individual or a group of people in a natural environment, and recording observations about the behaviour they witness

  Advantages

  • Can eliminate extraneous variables

  Disadvantages

  • Observer bias present
• Longitudinal study

  • Investigates a group of people over a period of time

  Advantages

  • Continual data collection

  Disadvantages

  • High costs
  • Longer research time
  • Unpredictable
• Correlation study

  • Examines wether a relationship exists between two or more variables without the researcher manipulating any of them

  Advantages

  • Helps understand the complex relationship between two variables

  Disadvantages

  • Does not show a casual relationship
  • No causation
• Non-scientific approaches include things like astrology. These are not based on science and are often labelled pseudoscience, they do not have a scientific foundation. (Put the opposite as scientific) No IV or DV is being measured or manipulated. no systematic approach no hypothesis.
• 1. Experiments test whether one thing, a phenomenon or a variable influences or causes a change in another thing or another variable. Cause and effect relationships.

  Non-experimental methods, often involve observation, and recording the behaviours of others. Non-experimental does not mean non-scientific, it means that the evidence is collected in ways that do not involve experiments.
• The scientific method involves a systematic approach to the planning conduction and reporting of research, usually in the form of experiments. With a scientific approach, researchers collect empirical evidence or data that enables them to draw valid conclusions based on the experiments. scientific method is based on verifiable observation or experience.
• 3. Features of experimental research methods

  Independent and dependent variables

  Directional and non-directional hypotheses

  Controlled variable DEFN⇒ a controlled variable is not changed throughout the experiment to ensure that the changes observed are the result of changes in the independent variable

  Uncontrolled variable ⇒ An uncontrolled variable is allowed to stay random since it would have no predicted effect on the outcome
• 4. Experimental and controlled groups

  The experimental group is the group that is subjected to the manipulation of the IV while those in the control group are not exposed to any change in the IV (maybe exposed to a placebo)
• 5. Placebo and experimenter effects

  A placebo is defined as a fake pill or procedure given as if it were a treatment, it is a pretend IV

  The placebo effect is a participant variable that can potentially affect both changes in the DV and the outcome of the IV.

  The experimenter effect is the experimenter’s variables can cause a bias in results. Prevented by double-blind procedures
• 6. Reliability and validity

  Reliability⇒ is a measure of the extent to which you would get the same result if the same measure were given to the same person under the same circumstances.

  Validity ⇒ refers to the extent to which the results reflect what the measurement instrument says it is measuring
• 1. Longitudinal and cross-sectional designs

  Cross-sectional methods, take into account age-related developmental changes by comparing children of different ages during the same time frame.

  Longitudinal methods study the same group of people at different points in time
• 1. Features of non-experimental (descriptive) research methods

  Non-experimental related to qualitative methods of research, they do not involve active manipulation, and cannot be changed for one or more of three reasons

  1. The variables cannot be modified by the experimenter (gender or age)
  2. Variables cannot be modified for ethical reasons (such as alcohol consumption or tobacco smoking)
  3. Not feasible to alter the variables (such as school or classroom placement)
• Non-experimental research designs are used when the researchers wish to understand or describe a phenomenon. they are not used to describe a pattern of results, but instead explain something that naturally occurs. Very flexible.
• 1. Case studies, surveys, correlational studies and archival research

  Correlation studies look at the relationship between variables

  Archival research is an examination of previously collected material held be places like libraries, governments, law courts and universities.
• Ethics in psychology research

  • based on the values of respect for human beings research merit, integrity, justice, and beneficence (the benefits of the research outweighing the risks)
• Privacy⇒ It is the right of protection from unwanted intrusion by the government or other people into one’s affairs. Protection of privacy related to the type of personal information that is collected stored and shared and who can have access to that information
• Anonymity⇒ The protection of people’s identities where when providing information for research they do not disclose their name