Not exposed to the independent variable, provides a baseline measure for comparison
Experimental group
Exposed to the independent variable, determines whether the IV made a change in the DV
Allocation
When participants are assigned to the different groups in an experiment
Research hypothesis
A testable prediction about the relationship between two or more variables
Research Population
The entire group of research interest that the sample is taken from
Population vs. Sample
Population - The entire group of research interest
Sample - Smaller group of research participants taken from the larger population
Convenience sampling
Surveying people at the entry of Chadstone shopping centre
Advertising study on social media and drawing sample from people who respond
Convenience sampling
Involves selecting participants who are readily available without any attempt to make the sample representative of a population
Random sampling
Ensures every member of the research population has an equal chance of being selected to be part of the sample
Stratified sampling
Involves dividing the population into groups/strata based on specific categories and then selecting a sample from each strata in the same proportion that they occur in the population
Representative sample
Reflects the characteristics of the wider research population
Biased sample
A sample that does not adequately represent the key characteristics of its population
Allocation
The process of assigning participants to different groups in an experiment
For any two variables which are measured in a correlational study, there are three possible relationships between them — positive, negative and zero (no relationship)
Positive correlation
Two variables change in the same direction - as one variable increases, the other variable tends to increase (and vice versa)
Negative correlation
Two variables change in opposite directions - as one variable increases, the other variable tends to decrease (and vice versa)
Zero correlation
There is no relationship between two variables
Quantitative data
Information that is expressed numerically, information about the 'quantity' or amount of what is being studied
Examples of quantitative data include raw data that have not been analysed in any way, such as lengths or weights of prematurely born infants, and percentages of participants who respond with 'Yes' or 'No' to survey questions
Simulation
Realistic way to investigate behaviour and/or mental process of someone in that environment
Simulation has the limitation of artificiality - difficult to generalise the results to a real life setting as participants may behave differently knowing that they are in a simulation
Types of data
Quantitative
Qualitative
Quantitative data
Information that is expressed numerically, about the quantity or amount of what is being studied
All types of mental experiences and behaviours can be described in quantitative terms as amounts or numbers
Objective data
Information that is observable, measurable, verifiable and free from the personal bias of the researcher
Subjective data
Information that is based on personal opinion, interpretation, point of view or judgment
Discrete data
A type of quantitative data that includes non-divisible figures and statistics you can count
Continuous data
A type of quantitative data that represents precise measurements of nearly any numeric value
Descriptive statistics
Measures of central tendency
Extraneous variables
Variables that aren't the IV or DV but can have an unwanted influence on the IV
Examples of participant variables
Learning ability
Mood
Weight
Athletic ability
Age
Gender
Intelligence
Personality
Memory ability
Examples of situational variables
Use of non-standardised instructions
Use of non-standardised procedures
Experimenter effects
Controlling extraneous variables
1. Random allocation
2. Random sampling
3. Use of standardised procedures
4. Randomisation
Confounding variable
A variable other than the IV that may have an unwanted effect on the DV which can be confused with that of the IV
Internal validity
The extent to which a measure accurately measures what it is supposed to be measuring
External validity
The extent to which the results of a study can be generalised to other situations and people
Conclusion
A decision about what the results obtained from a research investigation mean
Generalising conclusions to the research population
Stating how the findings of the experiment/study conducted on the sample can apply to other people in the research population