Transcript Research Methods - Glossopdale Community College

Formulating hypotheses
 Most research starts with an idea about something that might be
happening.
Hypothesis – a testable statement about the relationship between two
variables.
Variable – a factor or thing that can change
Independent variable – the IV is the variable that the researcher
manipulates.
Dependent variable - the variable that the researcher measures
Condition – An experiment is usually organised so there are two trials,
after which the performances of the participants are compared.
The experiment is looking at the effect of _______________ (IV) on
the _______________ (DV)
Design
 Independent groups – All the people are randomly
assigned to two or more conditions. One group is exposed
to the IV and the others are not. The results from the two
groups are compared
 Repeated measures – The participants remain in one
group and go through two conditions one with the IV and
one without. The results between the two conditions are
compared
 Matched pairs - The people are tested before the
experiment and matched for certain characteristics. Within
each pair one of the participants is tested with the IV and
the others without and the results are compared.
 Standardised procedures - a set order of carrying out the
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experiment that is applied to all the participants when necessary
Random Allocation – when PPs are randomly assigned to the
conditions by chance
Order effects – this occurs when PPs performance in the second
part of the study is better because they have practiced in the fits
condition.
Counterbalancing – a procedure for balancing out the order in
which PP complete both conditions in a study.
Extraneous Variable – a variable that is not the IV and may
affect the DV
Control - Making sure the procedure is the same, to prevent
EV’s affecting the results.
Randomisation – using chance to produce an order for a
procedure. This removes any biases.
For example deciding which order 20 words should be presented.
Randomisation would mean that the words were pulled out of a
hat to decide which order they go.
Instructions given to the participants in the
experiment should be as follows:
 Briefing - introduce yourself to the participants and explain
what is going to be happening, gain consent and ensure
they are happy to commence. Care should be taken to avoid
giving too much away, however all ethical considerations
must be addressed.
 Standard instructions – the clear instructions about exactly
what is required in the experiment, with demonstrations of
needed.
 Debriefing - Explain in detail what the study was about and
discuss the results with PPs. Ensure they are still happy
that they took part and address any other ethical issues
such as deception.
Research in natural and experimental settings
 Research is scientific and takes place in a controlled
environment, this has a number of advantages and
disadvantages.
Control of EVs means it is easier to see cause and effect.
Experiments are controlled and can be replicated - by repeating a
study it can checked that it was the real result and not a fluke
Experiments are objective because many are set up in such a way that
the researcher is not present.
The setting can be very artificial and tasks can be unrealistic - there can
be a lack of ecological validity. It is possible to overcome this by using a
more natural setting
PPs usually know they are in the experiment and this could affect the
behaviour they produce.
Sampling
 Participant – a person who is selected to take part in the study
 Sample – a small group of people who represent the target population
 Target population - the larger group of people the psychologists
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wishes to study
Representative – the sample of PPs is made up of people who have
the same characteristics and abilities of the target population.
Generalised – the results from the study can be said to apply to the
target populations
Random sample – every member of the target population as equal
chance of being selected for the experiment (can be hard to do
properly)
Opportunity sample – people who are members of the target
population and who are willing and able to take part in the study
Sampling methods
 Random sample- pulling names out of a hat where each person has
an equal chance of being selected. If the target population is small then
this can be done fairly easily, however once the target population gets
too large to handle this method is no good
 Opportunity sample – means choosing people who are willing and
able to take part. Often these people are friend or students at university
and so they do not always represent the target populations.
 Systematic sample – involves selecting every nth person. e.g. from a
year list every 8th person is selected. This is not a random method as all
PPs do not have equal chance of selection. It is unbiased as the
researcher does not select the people.
 Stratified sample – the population is sorted and then people
randomly selected from the groups e.g. divide students into year groups
and then randomly select from year 7, 8 9 and so on. This is good as the
sample will have students from all year groups.
Data Analysis
How do you deal with data?
Data analysis
Raw data - scores collected from the study
Anomalous data – an extremely high or low score that does
not match the other results in a set of scores.
Calculating Averages
Mean - a statistic calculated by adding them all up and
divide by the number there are
Calculate the mean for these frequencies:
25,29,24,26,20,25,20,24,21
Answer___________________
How do you deal with data?
Mode -the most frequently occurring value
This is the number which occurs MOST OFTEN
22,25,26,22,62,42,66,22,21,23,22
Answer_____________________
Median – the middle value when all the numbers are
placed in order, from the lowest to the highest.
21,25,24,26,21,21,25,25,26,28,29
_____________________
Answer
How do you deal with data?
The Range -Take the highest from the lowest
22,24,26,21,28,29,24,2,25
Answer
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Percentages – a proportion expressed as a fraction of 100
Boys
Running
15
Girls
12
hopping
2
Total ___
8
Total ____
skipping
3
standing
8
9
1
Add up the totals and then divide each figure into the total and multiple
by 100 to gain a %
Answer ______________________
Graphs
 Data can be presented graphically to enable conclusions to be made.
There are two main types of graph
Bar Charts
 Each bar represents separate categories and the frequency or amount
can be easily seen.
 Ensure you are able to read data from a bar chart, take your time to
work out what the axis measure.
Line Graphs
 This is often used to display data that are connected to each other.
Joining points show a relationship between the points.
Ethics
Competence
 Psychologist should only give advice they are qualified to give.
Responsibility
 Researchers must protect the participants from harm. The risks in
research should be no greater than the risks in everyday life.
 All PPs should be debriefed at the end of the study
Integrity
 Psychologist should behave with honesty and fairness in all their
interactions with people. They should consider whether the benefits of
research outweigh the cost to those involved.