REASEARCH METHODS INTRODUCTION Flashcards
experimental aim
statement of what researchers intend to find out in a study
What should an experimental aim be like ?
-clear and detailed
-outline the purpose of a study
What should an experimental aim not be
A question
Variables
Things that can be changed or altered such as a characteristic or a value
Operationalisation
means making them measurable/quantifiable. We must use operationalization to ensure that variables are in a form that can be easily tested.
What are the two types of variables ?
Independent- variable that the researcher changes
dependent -variable that is measured
What does it mean to operationalise variables ?
To make something measurable
Hypothesis
precise and testable statement of prediction about the outcome of an experiment
What are the two different types of hypothesis
-experimental
-alternative
What can the experimental hypothesis be ?
-directional -says which group will do better or worse
-non-directional -doesn’t state which group is better or worse
How do researchers decide to use a directional or non- directional hypothesis
-directional hypothesis - researchers tend to use this when a theory or the findings of previous research studies suggest a particular outcome
non-directional- When there is no theory or previous research or the findings from earlier studies are contradictory
What does Null predict
there will be no difference between groups/conditions
What should a good hypothesis include
-compare groups of independent variables
- The measurable dependant variable
Extraneous Variable
Any variable that could effect the dependent variable that is not the independent variable
4 Types of extraneous variables
-situational
-participant
-investigator effects
-demand characteristics
Situational variable
features of research situation that may influence a participators behaviour
examples of situational variables
-order effects -the order of tasks completed effects results
-heat
-time of day
What is counter balancing
A technique used to deal with order effects when using a repeated measures design
Two ways to counterbalance
-Standardise everything -using the exact same formulised procedures and instructions for all the participants in a research study
-ABBA - split participants into two groups , one group does everything in normal order , one group does everything in reverse order
Participant variables
the ways in which each participant varies from the other and how this could effect the results
examples of participant variables
-mood
-IQ
-anxiety
-concentration
How to control participant variable
Participant variables can be controlled using random allocation to the conditions of the independent variable.
However also
depends on the experimental design
Investigator effects
The experimenter unconsciously conveys to the participants how they should behave
- this is called experimenter bias
What is the experimenter often unaware of
the experimenter is often unaware of the influence which they are exerting
What are the two ways to control investigator effects
-double blind design
-inter-rater reliability
what is double blind design
both the participants and the person conducting the experiment are blind to the aims and hypothesis
What is inter-rater reliability
independent raters rate same behaviour as researcher
-check for agreement
Demand Characteristics
if participants know or guess the experimenters intention they may change there behaviour accordingly, which is not helpful to the experiment
What are the two ways to control demand characteristics
-single - blind design
-deception
What is single-blind design
-The participant is unaware of which condition they are in and/or the research aims
-This prevents participants from seeking clues about aims and reacting to them
what is deception
lying about the aims of the study or/and using distracting questions
Extraneous or confounding variables
when extraneous variables are not controlled by the experiment they become confounding variables that can damage the validity of the experiment
EV-COULD EFFECT THE EXPERIMENT
DV-PROBABLY HAS EFFECTED THE EXPERIEMNT
Experimental designs
The way in which participants are allocated to different conditions in an experiment for comparison
what are the different types of experimental designs
independent groups
repeated measures
matched pairs
Independent groups
-different participants take part in different conditions
-usually participants are randomly allocated to each condition
independent groups - STRENGTHS
-prevents order effects
-less likey to guess aims /hypothesis of the experiment
-prevents demand characteristics
independent groups - LIMITATIONS
-more people needed than with repeated measures
-more time consuming/repetitive
differences between participants in group may effect results, e.g. variations in age/gender
Repeated measures
every participant takes part in every condition (their results are compared to themselves
Repeated measures -STRENGTHS
-same participants are used in each condition (individual differences are decreased)
-fewer people needed
REPEATED MEASURES-LIMITATIONS
There may be order effects . This limitation can be controlled by counterbalancing
Matched pairs
-different but similar participants are used in each condition
-they are matched on variables relevant to the study
-monozygotic twins can be good for this as they are already perfectly matched
matched pairs-STRENGTHS
reduces participants variables because the researcher has tried to pair up participants so that each condition has people with similar abilities and characteristics
-avoids order effects and so counterbalancing is not necessary
Matched pairs -LIMITATIONS
-if one participant drops out you loose two participants data
-very time consuming trying to find closely matched pairs
-impossible to match people exactly even identical twins
What are the different types of sampling
-random sample
-opportunity sample
-volunteer sample
-systematic sample
-stratified sample
Population
Large group of individuals who the researcher may be interested in studying
for example students or adults with Tourette’s
Target population
This is the desired sub-group of the population to be studied e.g. students or adults with Tourette’s in England
Sample
These are the group of people who take part in the research .
These are drawn from the TARGET POPULATION and is presumed to be representative of the population
Random Sample
All participants have an equal chance of being selected
Random sample-STRENGTHS
-is free from researcher bias (no influence of who can be selected )
Random sample-LIMITATION
-time consuming and can be difficult to conduct
-no guarantee they are representative
opportunity sample
Those people who are available at the time and willing to take part
opportunity sample-STRENGTHS
-it is a quick and easy way of choosing participants and is convenient
Opportunity samples-LIMITATIONS
-researcher bias -could approach people who look helpful
-unrepresentative of target population
Volunteer sample
Participants put themselves forward to be part of a sample (self selection)
Volunteer sample-STRENGTHS
-It is easy and requires minimal input so is less effort and less time consuming for the researcher
-Could produce more committed individuals which could be good if the task is boring/long
-no experimenter bias
Volunteer sample-LIMITATION
-volunteer bias
- type of person
Systematic sampling
Every Nth member of the target population is selected to take part.
Systematic sampling-STRENGTHS
-Avoids researcher bias as once the system has been established the reasearcher has no influence over who is chosen
Systematic sampling-LIMITATION
-can also be difficult to achieve , time consuming
-no guarantee it will be truly representative
Stratified sampling
The researcher identifies the different types of people that make up the target population and work out the proportion needed for the sample to be representative
stratified sampling-STRENGTHS
-avoids researcher bias
-designed to be more representative of the population
Stratified sampling-LIMITATIONS
-stratification is not perfect - the identified strata cannot reflect all the ways people are different , so complete representation of the target population is not possible
-difficult to have complete list of general population
What are the four types of experiments
Laboratory
Field
Natural
Quasi
lab experiments
lab experiments are conducted in highly controlled environments - this is not always a literal lab
-It could be in a classroom that the conditions have been controlled in.
*
Field experiments
Field experiments are conducted in a real day setting in the field (the real world not a field)
the experimenter Still manipulates the IV in this type of experiment.
natural experiments
natural experiments are when the researcher takes advantage of a naturally securing independent variable
It is called natural because the IV would have occurred weather the experimenter was interested or not
- the setting for this type of experiment does not have to be natural
Quasi experiements
-Quasi experiments are when the reasercher does not control the IV,
-the IV is a pre-existing difference between participants
-For example, gender or age
-Quasi experiments cars occur in lab conditions
Lab experiemts -STRENGTHS
High control of extraneous variables allows cause & effect to be established
-This type of experiment is highly controlled, this makes accurate measurements possible
This type uses a standardised procedure a is easy to replicate.
lab experiments -LIMITATIONS
It is likely participants will know they are being studied in this type of experiment, which can pose a problem because of the Hawthorne effect.
Demand characteristics could potentially be an issue particularly for this type of experiment
the setting of this type may not reflect real life and
therefore may lack ecological validity
natural experiments-STRENGTHS
very useful in studying phenomena that might be unethical to manipulate
natural experiments-LIMITATIONS
As the participants cannot be randomly allocated to these groups , there is a strong likelihood of confounding variables
-this type of study the researcher has no control over independent variable as it will have occurred in everyday life
Field experiments - STRENGTHS
This type of experiment has high ecological validity because it is done in the participants environment
This type of study is covert, there is much less chance of demand characteristics occurring.
Field experiemnts-LIMITATIONS
It is more difficult to control extraneous variables in this type of experiment, making it harder for other researchers to replicate
This type of method could be potentially time consuming and expensive compared to other methods
quasi-STRENGTH
quasi-LIMITATION
What are the 5 ethical issues ?
-informed consent
-right to withdraw
-deception/debrief
-protection from harm
-confidentiality / privacy
