Exta Bits (experiments) Flashcards
What are the three measures of central tendency?
Mean
Median
Mode
What are the three measures of dispersion?
Range
Variance
Standard deviation
How d you calculate variance?
Mean score per condition in experiment
Subtract the mean score for each individual score
Square each difference value
Add all the d2 values together
Calculate the man of the d2 scores by adding together and dividing by n-1
How do you calculate standard deviation?
Mean score per condition in experiment
Subtract the mean score for each individual score
Square each difference value
Add all the d2 values together
Calculate the man of the d2 scores by adding together and dividing by n-1
Square root answer
Square root variance
What type of data is represented on a histogram?
Continuous
Emphasises category width and frequency
What inferential statistical test should you use with NOMINAL LEVEL DATA and INDEPENDENT MEASURES DESIGN?
Chi Squared
What inferential statistical test should you use with NOMINAL LEVEL DATA and REPEATED
MEASURES OR MATCHED PARTICIPANT DESIGN?
Binomial sign test
What inferential statistical test should you use with ORDINAL LEVEL DATA and INDEPENDENT MEASURES DESIGN?
Man Whitney-U
What inferential statistical test should you use with ORDINAL LEVEL DATA and REPEATED MEASURES OR MATCHED PARTICIPANT DESIGN?
Wilcoxon Signed Ranks Test
What inferential statistical test should you use with ORDINAL LEVEL DATA and CORRELATION?
Spearman’s Rho
What parametric test should you use with INTERVAL/RATIO LEVEL DATA and INDEPENDENT MEASURES DESIGN?
Independent t-test
What parametric test should you use with INTERVAL/RATIO LEVEL DATA and REPEATED MEASURES OR MATCHED PARTICIPANT DESIGN?
Related t-test
What parametric test should you use with INTERVAL/RATIO LEVEL DATA and CORRELATION EXPERIMENT?
Pearson’s Product Moment
What are the three criteria that have to be met before using a parametric inferential statistic?
Interval level data
There is a normal distribution of the results
All groups in the research have similar variance
What is the purpose of statistical tests?
To tell you whether the alternative hypothesis has been supported
How is the standard level of significance written if it’s not been reached?
P>0.05
The probability the results are due to chance factors is greater than 1 in 20
SUPPORTS THE NULL HYPOTHESIS
How is the standard level of significance written is it is reached?
p<0.05
The probability the results are due to chance is less than or equal to 1 in 20
SUPPORTS ALTERNATIVE HYPOTHESIS
How is the standard level of significance written if it’s been exceeded?
P=<0.01
Probability the results are due to chance is equal to/less than 1 in 100
SUPPORTS ALTERNATIVE HYPOTHESIS
What is a type 1 error?
Researcher thinks they have found a significant result when they haven’t (false positive)
What is a type 2 error?
When researchers think they have not found a significant result when they have (false negative)
What does it mean when the normal distribution curve is negatively skewed?
So,e people have scored much lower than the others
What does it mean when the normal distribution curve is positively skewed?
A few people scored much higher than most/others
What does this symbol «_space; mean?
Much less than
What does this symbols»_space; mean
Much more than
What does this symbol mean ~
Approximately
What does reliability refer to?
The consistency of the test or measure
What is internal reliability?
The consistency of the measuring device (standardised and replicable procedure)
What is external reliability?
The consistency of a study’s findings
What is a split-half method?
Where the scores from one half of the questions and compared to the scores from the other half of the questions to see if participants scores consistent on both halves
What is the test-retest method?
Giving the participants the same test/measure at a different point in time to check whether their two scores are consistent
What is inter-rater reliability?
Two or more observers record the behaviour and then their results are compared to check their level of agreement (a high correlation between their scores of 0.8 or more would indicate high inter rater reliability)
What is face validity?
Whether a test appears to be measuring what it intends to
What is concurrent validity?
Whether a test or study measure gives the same results as another test or study measuring the same concept
What is concurrent validity?
Whether a test or study measure gives the same results as another test or study measuring the same concept
What is criterion validity?
Refers to how much one test or measure predicts the future performance of another test/meausre
What is construct validity?
Refers to whether the test/study actually measures the concept it sets out to measure (and extraneous variables are controlled for)
What is population validity?
Refers to the degree to which the sample used in the research is representative if a diverse group of people
What is ecological validity?
Refers to how accurately a piece of research reflect real life situations
What is REPRESENTATIVENESS
Refers to the sample in the research - if the sample is diverse and includes people from different ages, genders, occupations, education levels etc. it will be representative of the target population
What is GENERALISABILITY?
Refers to the results of the research - if the sample used in the research is biased and not very diverse the results can’t be generalised to everyone in the target population
What are DEMAND CHARACTERISTICS
Occur when participants work out the aim of the research either because it is obvious it as a result of repeated measures design. They may then change their behaviour and act in a way they think they researcher wants them to act
What is SOCIAL DESIRABILITY
Refers to when participants change their behaviour to present an image of being a good member of society or to fir in to social norms, rather than sowing their true behaviours
What is RESEARCHER BIAS
Refers to the way the researcher collects and interprets the results of the research. They may interpret behaviour based on their prior expectations and therefore this would lower the findings validity
What are RESEARCHER EFFECTS
Refers to the way that participants behaviour is influenced by the presence (and their characteristics) of the researcher
What are the 4 broad ethical guidelines?
Respect
Competence
Responsibility
Integrity
What requirements come under the ethical guideline respect
Informed consent
Right to withdraw
Confidentiality
What requirements come under the ethical guideline responsibility
Protection from harm
Debrief
What is an abstract?
It summarises the research/report
What is an introduction?
Discuses previous reports/research to link to
What does the method include?
Design, sample, materials/apparatus, procedure
What do the results include?
They contain raw data, graphs charts and explanations of what happened
What’s involved in the discussion?
The findings their implications and limitations
What is included in the appendicies?
Any relevant material used from the study
What must be included in citing an academic reference?
Authors (surname followed by initial of first name)
Year if publication of article
Article Title
Journal Title
Volume of journal
Issue number of journal
Page range of article
What is meant by peer review?
Academic articles need to be read and evaluated by experts in the same field before being published
so that they can ensure that the methodology used is robust (i.e. valid and reliable measures have
been used to collect the results).
What are the strengths of peer review?
Can be used to check that research will
be useful before it is funded.
Ensures only the most relevant and
robust research is published.
It ensures that only valid results are
published so the journals retain their
reputation.
What are the weaknesses of peer review?
Can take a long time.
Some reviewers may not pass research
that contradicts their own.
May not be possible to detect research
that has used false data.
What is meant by the study of cause and effect?
Where a researcher can show that one variable is actually
causing a change in another variable.
What is meant by falsifiability?
The ability, in principle, to prove a claim wrong
What is meant by objectivity?
When a claim is a matter of fact, rather than opinion
What is meant by replicability?
The ability to repeat a study and therefore test to see if its findings are reliable (the use of controls and standardised procedures make it more replicable)
What is INDUCTION
Empirical research is carried out and then a theory is developed to make sense of findings
What is DEDUCTION
A theory is developed and then empirical research is carried out to see if the theory is correct (i.e. supported by evidence)
What is hypothesis testing?
Based on a psychological theory, a prediction is made about
how participants would be expected to behave, which can be
tested through research (e.g. experiment, observation, etc.)
What is manipulation of variables?
When an independent variable is changed (manipulated) to
see what effect this has on a dependent variable (how it
affects behaviour)
What is standardiseation
The test conditions are kept the same for all participants
What are quantifiable measurements?
The use of numerical data, which can be used to compare
between conditions. This should be observable and objective.
What is interval/ratio data?
This is the highest level of data. Analysis is
made of the scores achieved by individual
participants. It involves the use of standard
universal scales (e.g. seconds, kilograms,
metres, etc.
What is ordinal data?
This is the medium level of data. Analysis is
made of individual scores achieved by
participants, but only in relation to each
other (i.e., what is analysed is their rank
position within a group
What is nominal data?
This is the lowest level of data. It is a
‘headcount’ of the number of participants
who do one thing as opposed to another.
What are the strengths of nominal data?
Quick and easy to obtain because it is just a
headcount
Can be displayed in pie charts (which can
be easily made sense of)
What are the weaknesses of nominal data?
Can only analyse the mode of data and
cannot calculate the mean or median
Cannot analyse measures of dispersion (such
as range and standard deviation)
Less precise as data is grouped into
categories (we don’t know how individual
participants scored)
What are the strengths of ordinal data?
Can calculate mean, median and mode as
measures of central tendency (so more
detailed)
Can also calculate measures of dispersion
Can calculate individual scores of
participants and see how they differ
What are the weaknesses of ordinal data?
Ordinal data can be subjective (as people
may interpret rating scales differently)
Although we can work out the rank order of
participants, we don’t always know the exact
difference between individual scores
Worse than nominal because:
More time consuming and complex to
analyse
What are the strengths of interval?
Can calculate mean, median and mode as
measures of central tendency
Can also calculate measures of dispersion
Can calculate individual scores of
participants and see how they differ
Better than ordinal because:
Scores can be compared directly as precise
values are recorded (i.e. you can see the
actual difference between scores rather
than just the rank position)
The scores are more consistent as the
same universal scale is used (e.g. a cm is
always measured in the same way)
What are the weaknesses of interval data.
Can only be used with concepts that are
measurable through universal scales (can’t
be used with attitudes, opinions, etc.)
Worse than nominal because:
More time consuming and complex to
analyse
