Experiments Flashcards
Lab experiment
an experiment conducted in a controlled environment
Field experiment
an experiment conducted in a natural environment with the IV being manipulated by the researcher
Quasi experiment
an experiment conducted (in a natural or lab setting) where the researcher has no control over the IV
Control condition
a level of the IV where everything is kept the same without anything being manipulated
Independent variable
the variable manipulated by the researcher
Dependent variable
the variable measured by the researcher
Extraneous variable
any variable other than the IV affecting the DV
Independent measures design
separate groups of people for each level of the IV
usually a control group and an experimental group
Repeated measures design
all participants take part in all the conditions
Matched groups/pairs design
participants are tested in terms of variables relevant to the study
participants are then matched and one member of each pair goes in each group
Controls
anything in an experiment kept the same across all conditions to prevent it from interfering with the results
Order effects
a byproduct of using a repeated measures design
the order of the conditions having an effect on the participants behaviour
Counterbalancing
a technique used to deal with order effects in a repeated measures design
divide the participants into two groups and have each group perform a slightly different task, so that any imbalance in the task is canceled out
Demand characteristics
cues that might indicate the study aims to participants
Researcher effects
when a researcher influences the outcome of any research they are conducting
Single blind trial
when the participants don’t know the aims of the experiment
Double blind trial
when the participants and the researcher don’t know the aims of the experiment
Researcher bias
when the researcher’s expectations influence the experimental design or data collection process
Alternative hypothesis
statement of a relationship between variables (there is a difference)
Null hypothesis
statement of no relationship between variables (there is no difference)
Two tailed alternative hypothesis
an alternative hypothesis with no direction stated
One tailed alternative hypothesis
an alternative hypothesis with a direction stated
Operationalisation
making variables clearly defined and measurable
Target Population
the people you would like to study
Sample
subset of target population which aims to be representative of that population
Opportunity sampling
selecting people that are available in that moment
Self - selected sampling
participants volunteer themselves for the study
Random sampling
putting all members of the target population into a lottery method so that every member has an equal chance of being selected
Snowball sampling
asking a group of participants to recruit other participants
Primary data
data collected first hand by the researcher
Secondary data
data collected by someone other than the researcher
Qualitative data
data in words
Quantitative data
data in numbers
Measures of dispersion
Range - lowest score minus highest score
Standard deviation - the spread of scores around the mean
Variance
a measure of how much values in a data set differ from the mean
squared
Standard deviation
a measure which shows how much the values in the data differ from the mean
unsquared
Informed consent
Researchers should obtain consent from the participants
Debrief
After the research is over, the aims, procedure and findings should be able explained to the participants
Protection from harm
Participants should not be placed in any significant danger
Deception
Participants should not be deliberately misled about the aims of the study
Confidentiality
Participants and the data obtained from them should be kept anonymous
Right to withdraw
Participants have the right to leave at any time in the study and remove their data
Measures of central tendency
Mean
Median
Mode
Raw data table
Table showing the data collected in the study before it has been processed by measures
Descriptive characteristics
An observational research method
