The fundamentals of psycology as a science

What is an independent variable?

The variable which is manipulated by the experimenter

What is a variable

Anything that varies

Dependant variable

The outcome measured by the experimenter

What are covariables

Two variables measured by researcher but are not manipulated due to ethical reasons

How are these variables used in an experiment vs a correlation?

In an experiment they are looking at difference between the conditions by changing the independent variable.

Correlations look at the relationship between the conditions and do not manipulate the co-variables.( V1 does not effect the result of V2 there is only a relationship due to external factors)

What is an operational defenition?

The precise way we will measure a variable/ how we will measure the variable. Eg instead of memory recall we would measure it using the score obtained on a memory recall test.

What are extraneous variables and confounding variables?

Variables which might have an effect on the dependent variable which must be controlled.

Uncontrolled variables that have effected the results.

What is reliability?

The consistency of the results determines its reliability. This is tested by repeating research, which is called replication.

What is validity

How accurate to the true value a set of results are

What are the different sources of extraneous variables in psychological research and one way to fix them

Situational variables are variables in the research condition which can effect the DV, standardise procedures and instructions so that participants environment are all the same and unaffected or do pilot studies to materials to identify problems before the actual study.

Participant variables come from the participant which affect their performance e.g. high IQ or poor memory etc, this can be controlled through random allocation of participants so differences can be assumed to be balanced out across conditions.

Order effects- the effect the order at which tasks are carried out has on the result due to fatigue or memory from rehearsal, counterbalancing is used to control ABBA.

Demand characteristics are cues participants may receive that indicate the purpose of the research e.g. facial expressions or wording of questions being obvious, to control low level deception is used for example random questions to throw off the purpose.

Researcher effect- hoe the researcher may intentionally or unintentionally effect results due to expected outcome of experiment- this can be controlled by standardising procedures and instructions so no bias can be created.

What is an alternate hypothesis ( Ha)

A prediction in the form of a testable statement that can either be experimental or correlational.

Experimental hyp vs correlational hyp

E predicts the cause and effect relationship between IV and DV and is established using an experiment

C predicts the association between 2 co variables

Ha predicts the direction of an outcome by using what types of hypothesis

Directional ( one tailed) predicts direction of correlation e.g. in an experiment people who consume alcohol will have significantly lower scores than people who don’t

In a correlation there will be a significant positive correlation/ negative correlation etc

Non directional ( two tailed) predicts there will be a difference or correlation with no direction eg the will be a significant difference ( experiment) or correlation between… ( correlation)

What’s a null hypothesis

Predicts that any difference the researcher gets are due to chance and not significant or any correlation is not significant and is due to chance. There is always one that comes with alternate hypothesis

How do we accept hypotheses

Use statistical techniques to check if they are significant or not ( whether they were due to chance) and then decide if null hypothesis is accepted.

What is target population

Representative sample

Sampling bias

Particular group we are interested in studying Which we draw our sample from

Group of participants drawn from argent population which is typical of target population

When a sample becomes weighted because of over representation of one group of people so can be generalised from

Sampling techniques

Random sampling every member has equal chance of being selected means its unbiased but can become biased by chance

Opportunity sampling selecting participants available at time of study so is quick and convenient but is biased

Volunteer samples- consciously put themselves forward ethical easy but biased

Stratified sampling diving population into sub categories and members selected in proportion , sampling bias

What is a questionnair

How to design one

Self report data collection method given to participants in a standardised manner questions about beliefs and attitudes

Questions should be fit for purpose few as possible , clear concise short objective no leading questions

Filler questions for deception to avoid demand characteristics

Sequence questions so easy to hard or sensitive

Standardise

Pilot studies

Ethical issues

Closed question responses

Categories of response

Identify characteristics from lists

Likert scale how much agree or disagree

Ranked scale item

Semantic differential scales

Strengths and weaknesses of questionnaires

Highly reliable control extraneous variables researcher doesn’t have to be present easy quantative data to analyse cheap

Closed questions limit validity, demand characteristics socially desirable answers, misunderstand questions,