Features shared by psychological research

1. Theoretical framework 2. Standardised procedures 3. Generalisability 4. Objective measurement

Psychological Research Methods

1. Experimental 2. Descriptive - case study - naturalistic observation - survey research 3. Correlational

Description

Being able to summarise data your research has produced to make the events and relationships easily understandable

Prediction

Using the outcome of research to identify what would happen given the same circumstances

Understanding

Identifying why that would happen

Evaluating a study

1. Does the theoretical framework make sense? 2. Is the sample adequate and appropriate? 3. Are the measures and procedures adequate? 4. Are the data conclusive? 5. Are the broader conclusions warranted? 6. Does the study say anything meaningful? 7. Is the study ethical?

Theory

A systematic way of organising and explaining observations.

Hypothesis

A tentative belief about the relationship between two or more variables.

Variable

Phenomena that vary or change across individuals or circumstances

Independent variable

The variables be experimenter manipulates

Dependent variable

The participants responses

Conditions

Different possible variations of the independent variable presented to the participant

Measure

A concrete way of assessing a variable

Confounding variable

A variable that could produce effects that might be confused with the effects of the independent variable

Reliability

A measures ability to produce consistent results

Retest reliability

The tendency of a test to yield relative similar scores for the same individual over time.

Internal consistency

Several ways of asking the same question yield similar results.

Interrater reliability

If two different interviewers rate an individual both should give the person similar scores.

Validity

The measures ability to assess the variable it is supposed to assess.

Scientific approaches three goals

Description, Prediction and Understanding

Independent variable

Variables manipulated by the experimenter, which are outside the participants control.

Dependent variable

The response the experimenter measures to see whether the manipulation had an effect.

Code of ethics

1. Informed consent 2. Ensure welfare of participants 3. No excessive cash rewards 4. Confidentiality 5. Inform participants afterward if deception was used 6. Minimise discomfort to animals 7. Ensure approval of appropriate body

Conditions

Different possible variations of the independent variable presented to the participant

Demand characteristics

The ways participants perceptions of the researchers goals influenced their responses

Continuous variable

A variable that can be placed on a continuum

Categorical variable

A variable comprised of groupings or categories

Standard procedures

Exposing participants in a study to as similar procedures as possible

Population

The larger group to whom findings should be applicable

Sample

A subgroup of the population

Representative

Conclusions drawn of the subgroup are likely to be true of the population. The sample accurately represents the population.

Generalisability

The applicability of the findings to the entire population of interest

Participants

Individuals who participate in the study

Sampling bias

Occurs when the sample is not representative of the population as a whole

Valid

To be valid the studying must meet two criteria. One. Convincingly test hypothesis. Two. Findings must be generalisable outside the laboratory.

Internal validity

Study must employ methods that convincingly test the hypothesis

External validity

The findings can be generalised to situations outside the laboratory

Validation

Demonstrating that a measure consistently relates to some objective criterion, or to other measures that have already demonstrated their validity

Error

Discrepancy between the phenomena is measured and the phenomena as it really is

Experimental research

Investigators manipulate some aspect of the situation and examine the impact on the way participants respond

Operationalising

Turning an abstract concept into a concrete variable defined by some set of actions or operations

Control group

A neutral condition in which participants are not exposed to manipulation

Blind studies

Participants are kept unaware of important aspects of the research

Placebo effect

Simply believing a treatment can be effective

Single blind study

Only the participants are kept blind

Double-blind study

Participants and researchers are both kept blind

Descriptive statistics

Away of describing the findings that summarises the essential features

Inferential statistics

Drawing inferences from the sample to the population as a whole

Quasiexperimental

Shares the logic in many features of the experimental method but does not allow as much control over variables

Descriptive research

Describes phenomena as they already exist rather than manipulating variables to test the effects

Case study

An in-depth observation of one person or a small group

Researcher bias

Results in systematic errors in measurement due to investigators seeing what they expect to see

Naturalistic observation

The in-depth observation of a phenomena in its natural setting

Survey research

Asking questions of a large sample of people

Interview

Researchers ask questions using a standard format

Questionnaire

Participants fill out themselves

Random sample

A sample selected from the general population in a relatively arbitrary way that does not introduce any systematic bias

Stratified random sample

Specifies the percentage of people to be drawn from each category of the population, then randomly select participants

Correlational research

Assesses the degree to which two variables are related, in an effort to see whether knowing the value of one can lead to prediction of the other

Correlate

To assess the extent to which a variable being high or low on one measure predicts being high or low on the other

Correlation coefficient

Measures the extent to which two variables are related

Positive correlation

The higher individuals measure on one variable, the higher they are likely to measure on the other

Negative correlation

The higher individuals measure of one variable, the lower they are likely to measure on the other

Correlation matrix

A table representing the correlations among a number of variables

Neroimaging techniques

Uses computer programs to convert data taken from brain scanning devices into visual images of the brain

Electroencephalogram (EEG)

Measures electrical activity towards the surface of the brain

Computerised axial tomography (CAT)

Rotating x-ray tube around a person's head, producing a series of x-ray pictures

Magnetic resonance imaging (MRI)

Uses magnets instead of x-rays

Positron emission tomography (PET)

Requires a small injection of radioactive glucose into the bloodstream. The computer images these as they are used by the brain

Functional magnetic resonance imaging (fMRI)

Uses MRI to watch the brain as individuals carry out tasks

Informed consent

The participants ability to agree or refuse to participate in a study

Deception

We participants are not informed of the aims of the investigation until the end of the study

Critical thinking

Carefully examining and analysing information to judge its value as well is considering other views and explanations before accepting the truthfulness of that information

Open-mindedness

Considering all sides of an issue

Objectivity

Taking an impartial and disinterested approach

Scepticism

Always questioning assumptions or conclusions and analysing whether the evidence presented supports the results

Straw man approach

Fallacy that involves authors deliberately attacking an opposing argument in order to strengthen their own

Appeals to popularity

The fallacy that popular and widespread arguments are true

Appeals to authority

The fallacy that an argument must be true because of the authority of the person making it

Arguments directed at the person

The approach in which authors try to strengthen their own position by attacking the authors of alternative arguments

Context of justification

In which hypothesis are tested empirically

Context of discovery

In which phenomena are observed, hypothesis framed and theories built

Descriptive statistics 2

Summarise qualitative data in an easily understandable form

Inferential statistics 2

Tells whether the results reflect anything other than chance

Histogram

A graph that plots ranges of scores along the X axis and the frequency of scores in each range on the Y axis

Frequency distribution

A method of organising data to show how frequently participants received each of the many possible schools

Measures of central tendency

Provide an index of the way a typical participant responded to a measure

Mean

The statistical average of the scores of all participants

Median

The score that falls in the middle of the distribution of scores

Mode

The most common score observed in the sample

Variability

The extent to which participants tend to differ from one another

Range

Shows the difference between the highest and lowest scores

Standard deviation

The amount the average participant deviates from the mean of the sample

Normal distribution

Scores of most participants fall within a bell curve distribution and progressively fewer scores at either extreme

Percentile scores

Indicate the number of scores that fall below a score

Statistical significance

A test to determine whether positive results have occurred simply by chance

Probability value (p-value)

Represents the probability that positive findings were chance. The smaller value the more certain the results

Effect size

Required to understand the magnitude of the experimental effect or strength of relationship

Chi-square test (x2)

Compares the observed data with the results that would be expected by chance and tests the likelihood that the differences between observed and expected are accidental

T-test

Comparing the means scores of two groups

Analysis of variance (ANOVA)

Used to compare means test of two or more groups, to assess the likelihood that mean differences between the groups occurred by chance