Research methods:
Key Terms:
Research Aim - A general statement that tells the purpose of the investigation
Hypotheses - A prediction that is clear, precise and testable stating the relationship between
variables. When writing a hypothesis you write the independent variable before the dependent
variable.
Independent variable - The variable that is changed
Dependent variable - The variable that is measured
Operationalisation - When you state your variable and how to measure it
Alternate hypothesis - Relationship between variables
Example: Temperature affects the amount of work completed
Null hypothesis - No relationship between variables
Directional (one-tailed) hypothesis - Predicts the effect of the independent variable on the
dependent variable. It predicts which direction the change will take place. (i.e. greater, smaller,
less, more)
In a good experiment the only thing that will cause a change in DV would be the IV as then the
researcher has shown cause and effect.
Non-directional (two-tailed) hypothesis - Predicts that the independent variable will have an
effect on the dependent variable, but the direction of the effect is not specified. It just states that
there will be a difference.
An Extraneous variable is an extra variable that interferes with the IV and DV
Types of Extraneous Variable:
● Participant Variables such as skill, ability, mood or concentration that influence
performance.
● Situational Variables are things in the environment that affect performance like
temperature
● Demand Characteristics are when participants unconsciously change behaviour due to
picking up on the purpose of the study
● Investigator Effects include factors such as giving extra information to one participant
or being nice to one participant.
Demand characteristics are controlled through single-blind procedures and deception.
Investigator effects are controlled through double blind procedures and inter-rater reliability.
, Social Desirability - Changing characteristics to try to fit in
Standardisation - Procedures in research are kept the same so it can be replicated
successfully
Randomisation - The process of assigning participants to treatment and control groups,
assuming that each participant has an equal chance of being assigned to any group. Reduces
bias.
Confounding Variable - Variables that the researcher failed to control, or eliminate, damaging
the internal validity of an experiment
Mundane Realism - How likely it is to see in the real world
Types of experiments:
● Lab Experiments are done in controlled environments and deliberately change IV and
measure DV. can easily control extraneous variables.
+ Include high internal validity as well as easy replicability
- Participants are aware of study and includes an unnatural IV
● Field Experiments take place in natural settings but still change IV and measure DV.
+ Participants are unaware with a relaxed environment
- Is difficult to control extraneous variables and may lack realism.
● Natural Experiments have no IV manipulated but DV is recorded and can occur in lab
or natural settings.
+ Researches real problems and effects
- lacks random allocation and can only include natural variety
● Quasi Experiments take place in a lab setting with no IV manipulation because it occurs
naturally like gender.
+ Uses comparison of people
- DV may be artificial reducing realism
Key Terms:
Research Aim - A general statement that tells the purpose of the investigation
Hypotheses - A prediction that is clear, precise and testable stating the relationship between
variables. When writing a hypothesis you write the independent variable before the dependent
variable.
Independent variable - The variable that is changed
Dependent variable - The variable that is measured
Operationalisation - When you state your variable and how to measure it
Alternate hypothesis - Relationship between variables
Example: Temperature affects the amount of work completed
Null hypothesis - No relationship between variables
Directional (one-tailed) hypothesis - Predicts the effect of the independent variable on the
dependent variable. It predicts which direction the change will take place. (i.e. greater, smaller,
less, more)
In a good experiment the only thing that will cause a change in DV would be the IV as then the
researcher has shown cause and effect.
Non-directional (two-tailed) hypothesis - Predicts that the independent variable will have an
effect on the dependent variable, but the direction of the effect is not specified. It just states that
there will be a difference.
An Extraneous variable is an extra variable that interferes with the IV and DV
Types of Extraneous Variable:
● Participant Variables such as skill, ability, mood or concentration that influence
performance.
● Situational Variables are things in the environment that affect performance like
temperature
● Demand Characteristics are when participants unconsciously change behaviour due to
picking up on the purpose of the study
● Investigator Effects include factors such as giving extra information to one participant
or being nice to one participant.
Demand characteristics are controlled through single-blind procedures and deception.
Investigator effects are controlled through double blind procedures and inter-rater reliability.
, Social Desirability - Changing characteristics to try to fit in
Standardisation - Procedures in research are kept the same so it can be replicated
successfully
Randomisation - The process of assigning participants to treatment and control groups,
assuming that each participant has an equal chance of being assigned to any group. Reduces
bias.
Confounding Variable - Variables that the researcher failed to control, or eliminate, damaging
the internal validity of an experiment
Mundane Realism - How likely it is to see in the real world
Types of experiments:
● Lab Experiments are done in controlled environments and deliberately change IV and
measure DV. can easily control extraneous variables.
+ Include high internal validity as well as easy replicability
- Participants are aware of study and includes an unnatural IV
● Field Experiments take place in natural settings but still change IV and measure DV.
+ Participants are unaware with a relaxed environment
- Is difficult to control extraneous variables and may lack realism.
● Natural Experiments have no IV manipulated but DV is recorded and can occur in lab
or natural settings.
+ Researches real problems and effects
- lacks random allocation and can only include natural variety
● Quasi Experiments take place in a lab setting with no IV manipulation because it occurs
naturally like gender.
+ Uses comparison of people
- DV may be artificial reducing realism
