Psychologists do more than just wonder about human behavior:
they conduct RESEARCH
Two Types of Research Used in Two Types of Research Used in PsychologyPsychology
Applied ResearchApplied Research – clear and practical reasons and uses for clear and practical reasons and uses for
researchresearch
– If a psychologist was trying to come up with a If a psychologist was trying to come up with a new behavior therapy to stop heroin use, it new behavior therapy to stop heroin use, it would be would be applied researchapplied research
Basic ResearchBasic Research – no immediate, real-world uses but explores no immediate, real-world uses but explores
interesting questionsinteresting questions
– Studying the differences between cultures and Studying the differences between cultures and physical beauty is an example of physical beauty is an example of basic basic researchresearch
Things that make research Things that make research scientificscientific
Research Must Be Research Must Be ReplicableReplicable
Must be able to be copied by others to get Must be able to be copied by others to get similar similar reliable data reliable data
the best and most reliable studies are replicated the best and most reliable studies are replicated over and overover and over
Things that make research Things that make research scientificscientific
Research Must Be Research Must Be PrecisePrecise Meaning research has to be to the point and easily Meaning research has to be to the point and easily
understood understood To be precise psychologists use To be precise psychologists use
Operational DefinitionsOperational Definitions a definition of terms so basic that when others a definition of terms so basic that when others
read your study they know exactly what read your study they know exactly what you are you are looking for or measuring looking for or measuring
Try to capture the essence of the concept so that Try to capture the essence of the concept so that others can observe itothers can observe it
Example – if you are trying to measure sense of Example – if you are trying to measure sense of humor – how would you make it humor – how would you make it
precise?precise? presence of more laughter, more smiling, presence of more laughter, more smiling,
greater number of laughs at jokesgreater number of laughs at jokes
Operational Definitions• Explain what you
mean in your hypothesis.
• How will the variables be measured in “real life” terms.
• How you operationalize the variables will tell us if the study is valid and reliable.
Let’s say your hypothesis is that chocolate causes violent behavior.
• What do you mean by chocolate?
• What do you mean by violent behavior?
What can cause research to What can cause research to go wrong??go wrong??
What exactly do I What exactly do I mean by bias??mean by bias??
BiasBias Any influence in research that unfairly increases the Any influence in research that unfairly increases the
possibility we will reach a particular conclusion possibility we will reach a particular conclusion
Types of BiasTypes of Bias Researcher Bias, Confirmation Bias, Researcher Bias, Confirmation Bias,
Experimenter BiasExperimenter Bias when when researchersresearchers look for and accept evidence that look for and accept evidence that
supports their beliefs and supports their beliefs and ignoreignore or or rejectreject evidence evidence that prove false their beliefsthat prove false their beliefs
Participant Bias (or subject bias)Participant Bias (or subject bias) when when research participantsresearch participants respond in a certain respond in a certain
way way because they know they are being because they know they are being observedobserved
act how they think the researcher wants them to actact how they think the researcher wants them to act
Hindsight BiasHindsight Bias when when researchersresearchers believe, after learning believe, after learning the the
outcome outcome of research, that they knew it all alongof research, that they knew it all along
Hawthorne Effect• the term is used to
identify any type of short-lived increase in productivity
• Just the fact that you know you are in an experiment can cause change
• So even a control group may experience changes and affect results of experiment
Whether the lights were brighter or dimmer, production went up in the Hawthorne electric plant.
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Scientific Method in Psychology
• Scientists develop theories through the scientific method
• The scientific method is the process used in psychology to discover knowledge about human behaviour and mental processes
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Scientific Method in Psychology (cont’d)
• The first step is to state the problem
• Psychologists must ask questions that can be answered
• The questions must be specific and defined in a clear way
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Scientific Method in Psychology (cont’d)
• The second step is to develop a hypothesis
• A hypothesis is an educated guess about the answer to the question that has been posed
• Hypotheses often emerge from theory
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Scientific Method in Psychology (cont’d)
• Step three is to design a study• Researchers must identify key variables and choose a suitable
method for investigation• Researchers also must consider how many participants will be
required and who the participants will be
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Scientific Method in Psychology (cont’d)
• The fourth step is collect and analyze data
• Techniques must be selected that do not bias the results
• Statistical methods help summarize the data that have been collected
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Scientific Method in Psychology (cont’d)
• The fifth step is draw conclusions and reporting results
• Researchers report results to the scientific community by making presentations at conferences or by publishing their findings in a journal
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Experimental Method
• Psychological research often takes the form of an experiment
• An experiment is a procedure in which researchers systematically manipulate and observe elements of a situation to test a hypothesis
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Experimental Method (cont’d)
• A variable is characteristic of a situation or a person that is subject to change or that differs within or across situations or persons
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Experimental Method (cont’d)
• The independent variable is manipulated by the experimenter
• The dependent variable is the behaviour or response that is expected to change because of the experimenter’s manipulation
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Experimental Method (cont’d)
• A sample is the limited number of people researchers select to be part of the experiment and who represent a larger group
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Experimental Method (cont’d)
• An operational definition is a definition of a variable in terms of the methods or procedures used to study that variable
• Studying defined as 20 minutes per day over three days is an operational definition
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Experimental Method (cont’d)
• Participants are the individuals who take part in an experiment and whose behaviour is observed and recorded
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Experimental Method (cont’d)
• The experimental group “receives” the independent variable
• The control group is a comparison group who are tested on the dependent variable but do not receive the independent variable
3 Types of Research you will 3 Types of Research you will have to know!!!have to know!!!
Descriptive ResearchDescriptive ResearchCorrelational ResearchCorrelational ResearchExperimental ResearchExperimental Research
Descriptive ResearchDescriptive Research
Any type of research that describes the “who, what, when, where” of a situation
NOTNOT concerned with causes or how something works onlyonly about describing what is going on
What is going on in this picture?
We cannot say exactly, but we can describe what we see.
This is called…
Research Type #1Research Type #1
3 Types of Descriptive Research
• The Case Study
• The Survey
• Naturalistic Observation
Descriptive Research Type #1The Case StudyThe Case Study
• Where one person (or situation) is observed and studied in depth to gather information.
What is the strength and weakness of using a case study to study a topic like this??
For example, if I wanted to study personality and abnormal behavior how would a case study go about it??
Case Studies
• A detailed picture of one or a few subjects.
• Tells us a great story…but is just descriptive research.
• Does not even give us correlation data.
The ideal case study is John and Kate. Really interesting, but what does it tell us about families in general?
Can study a behavior in depth and get Can study a behavior in depth and get quality quality info info on that caseon that case
The results of the case study are usually The results of the case study are usually
not not generalizablegeneralizable to the rest of to the rest of the the population. population.
One persons case would One persons case would notnot be a valid be a valid representation representation of the whole populationof the whole population
WeaknessWeakness
StrengthStrength
Descriptive Research Type #2The SurveyThe Survey
• Uses interviews or questionnaires to gather information like attitudes and beliefs
•The Good – Allows generalization– Cheap and anonymous– Can get a diverse and large
population
Has both pros and cons when Has both pros and cons when usedused
Survey Method: The Bad
• Social Desirability BiasSocial Desirability Bias – Give socially acceptable answers not truth
• Volunteer BiasVolunteer Bias– People who volunteer may not be representative
of whole population
• Problems with wording and answer Problems with wording and answer optionsoptions
How accurate would a survey be about the frequency of
diarrhea?
Descriptive Research Type #3 Naturalistic ObservationNaturalistic Observation
• Observing and recording behavior in natural environment – No interacting with subjects at
all – just an observer– “taking the lab into the field”
What are the benefits and detriments of Naturalistic
Observation?+ = natural behavior
- = observers may see different things- = can’t control the environment or outside factors
Field Trip
• We will stay together as we walk around the school grounds.
• We are to stay quiet and observe
• There is nothing special set up, I just want you to LOOK
How many signs in the hallway?How many paw prints around the school?How many times did you see the word Huskies?How many cars in the parking lot?Did a plane fly over?How many people did you pass?
Correlational Research
Explores relationships or links (correlations) between variables
Example – mothers smoking during pregnancy is “correlated”“correlated” with increased risk of SIDS in babies
Descriptive Research - - - describes Correlational Research - - - links or
relationships between things
Research Type #2
Correlational ResearchCorrelational Research• #1 Thing to remember in Correlational Research
Correlation does not equal causation!!!!!Correlation does not equal causation!!!!!• It is important to understand that CR does NOT
say that one variable causes another but rather that they are somehow related
There is a correlation between ice cream and murder rates. Does that mean that ice cream causes murder?
For Example…
Remember…correlation does not equal causation!!!!!
We may not be able to determine cause, but we can measure the
strength of a relationship…• Relationship of variables is measured using
correlation coefficientcorrelation coefficient– A statistical measure (a number) of A statistical measure (a number) of
strength of relationship of variablesstrength of relationship of variables • (ex. Ice cream and murder rates)
– Can vary -1.00 to +1.00Can vary -1.00 to +1.00 (more on this later)
• Correlations or relationships can go in two directions– Positive– Negative
Types of Correlation
Positive Correlation• The variables go in
the SAME direction.
Negative Correlation• The variables go in
opposite directions.
Studying and grades hopefully has a positive correlation.
Heroin use and grades probably has a negative correlation.
Experimental Research
Explores cause and effectcause and effect relationships by manipulating and measuring variables
Eating too many Onions causesBad Breath
Research Type #3
How do we explore cause and effect??
1. Form a Hypothesis – a testable prediction
2. Pick Population • The group who you are experimenting on- First by Random Selection - Then randomly assign them to one of two groups
- control group – those who do not receive the
experimental treatment- experimental group
– those who do receive the experimental treatment
3. Operationalize the Variables
4. Identify Independent and Dependent Variable
We set up, design, and run an Experiment
Operationalization Exercise
Independent VariableIndependent Variable Factors that are manipulated in an experimentFactors that are manipulated in an experiment
The variable that should cause something to happenThe variable that should cause something to happen
Dependent VariableDependent Variable The variable that should show the effect of The variable that should show the effect of
changing the IV changing the IV
the way you can figure this out is the way you can figure this out is …”…”IfIf……thenthen…”…” IfIf = IV = IV thenthen = DV = DV
- - “If students study for a quiz before going to “If students study for a quiz before going to sleep, sleep, rather than in the morning, then they rather than in the morning, then they will get will get higher test scores”higher test scores”
Experimenters try to hold everything Experimenters try to hold everything else constant so that the independent else constant so that the independent variable is the cause of the observed variable is the cause of the observed
effects but this doesn’t always happen effects but this doesn’t always happen because of…because of…
Independent Variable
• Whatever is being manipulated in the experiment.
• Hopefully the independent variable brings about change. If there is a drug in an
experiment, the drug is almost always the independent variable.
Dependent Variable
The dependent variable would be the effect of the drug.
• Whatever is being measured in the experiment.
• It is dependent on the independent variable.
Extraneous or Confounding Variables variables that you don’t count on that
could change or influence the DV you want to check for these to make sure they don’t mess up
what you are looking for with the IV
1. Determine the type of experiment: Blind vs. Double Blind
- blind – participants are kept in the dark about
purpose or about hypothesis- double-blind
– both the participants and researcher are kept in the dark - placebo
– an inactive pill that has no known effect (sugar pill)
2. Gather Data
3. Analyze Results
20 students randomly assigned to
experimental group
Wear headphonesdaily in study hall
Average grades atthe end of the quarter
40 students randomly selectedAll Study hall students(population)
Average grades atthe end of the quarter
Not allowed to wear headphonesin study hall
20 students randomly assigned to
control group
Hypothesis – students who are assigned to wear headphones in study hall will have higher average grades at the end of the quarter than those banned from wearing headphones
Sample
IV
DV DV