Unit 2 (B):Unit 2 (B):Non-Experimental Non-Experimental Research DesignsResearch Designs

Mr. McCormickMr. McCormickA.P. PsychologyA.P. Psychology

Do-NowDo-Now(In Journal)(In Journal)

Think of a Think of a psychological psychological phenomenon phenomenon that you would be that you would be interested to interested to researchresearch (a behavior, (a behavior, habit, disorder, etc.)habit, disorder, etc.)

Briefly Briefly describedescribe how you could how you could hypothetically hypothetically carry out your carry out your researchresearch

Pre-Research DecisionsPre-Research Decisions

Population:Population: All the cases in a group being studied, from All the cases in a group being studied, from

which samples may be drawnwhich samples may be drawn E.g. The entire CHS student body (2,000 E.g. The entire CHS student body (2,000

students)students)

Sample:Sample: Small group of participants, out of a total Small group of participants, out of a total

population, that a researcher studiespopulation, that a researcher studies Representative vs. Non-representativeRepresentative vs. Non-representative E.g. 200 CHS studentsE.g. 200 CHS students

Pre-Research DecisionsPre-Research Decisions

What might a What might a representative representative sample sample of of CHS studentsCHS students look look like?like?

How could we How could we effectivelyeffectively get a get a representative samplerepresentative sample of of CHS CHS studentsstudents??

Pre-Research DecisionsPre-Research Decisions

Random Sample:Random Sample: A sample that fairly represents a population A sample that fairly represents a population

because each member has an equal chance of because each member has an equal chance of inclusioninclusion

Non-ExperimentalNon-ExperimentalResearch DesignsResearch Designs

Naturalistic Observation:Naturalistic Observation: Observation of subject(s) in a natural setting Observation of subject(s) in a natural setting

without manipulating or controlling the situation without manipulating or controlling the situation (e.g. watching teenagers in a mall)(e.g. watching teenagers in a mall)

Case Study:Case Study: Intensive investigation of participant(s) (e.g. long-Intensive investigation of participant(s) (e.g. long-

term interviews, living with participants, journals, term interviews, living with participants, journals, video blogs)video blogs)

Survey:Survey: Information is obtained by asking many individuals Information is obtained by asking many individuals

a fixed set of questions (e.g. questionnaire on self-a fixed set of questions (e.g. questionnaire on self-reported attitudes or behaviors)reported attitudes or behaviors)

Non-ExperimentalNon-ExperimentalResearch DesignsResearch Designs

Longitudinal Study:Longitudinal Study: Studying a group of participants over a Studying a group of participants over a

number of years (e.g. following a group of number of years (e.g. following a group of high school freshmen throughout their high high school freshmen throughout their high school career)school career)

Cross-Sectional Study:Cross-Sectional Study: Studying groups of participants of different Studying groups of participants of different

ages and comparing them to draw conclusions ages and comparing them to draw conclusions about age (e.g. studying a group of freshmen about age (e.g. studying a group of freshmen and seniors)and seniors)

Non-ExperimentalNon-ExperimentalResearch DesignsResearch Designs

Think of an Think of an exampleexample in which each of in which each of the following the following research designs research designs would be most would be most effectiveeffective:: Naturalistic ObservationNaturalistic Observation Case StudyCase Study SurveySurvey Longitudinal StudyLongitudinal Study Cross-Sectional StudyCross-Sectional Study

CorrelationCorrelation

Correlation:Correlation: A measure of the extent to which two factors A measure of the extent to which two factors

vary together (and how well one factor predicts vary together (and how well one factor predicts the other)the other)

Does Does not not demonstrate causationdemonstrate causation Can be Can be positivepositive or or negativenegative Can be Can be illusoryillusory (appears to be relationship (appears to be relationship

where none exists)where none exists) Measured with Measured with scatterplotsscatterplots Measured by a Measured by a correlation coefficient “r” correlation coefficient “r” (-1 (-1

to +1)to +1)

CorrelationCorrelation

What What naturally-naturally-existing existing

correlationscorrelations

can you think of?can you think of?

CorrelationCorrelation

Positive Correlation:Positive Correlation:

DirectDirect relationship relationship

Both Both factors factors increase increase togethertogether; ; BothBoth factors factors decrease decrease togethertogether

E.g. Amount of sleep E.g. Amount of sleep and GPAand GPA

Right: Perfect Positive Right: Perfect Positive Correlation (r=+1.00)Correlation (r=+1.00)

Height and Height and Temperament in MenTemperament in Men

r=+0.63

CorrelationCorrelation

Negative Negative Correlation:Correlation:

InverseInverse relationship relationship

One factorOne factor increases increases, , while the while the other other decreasesdecreases

E.g. Physical exercise E.g. Physical exercise and fat contentand fat content

Right: Perfect Negative Right: Perfect Negative Correlation (r=-1.00)Correlation (r=-1.00)

CorrelationCorrelation

What do you think a What do you think a scatterplotscatterplot would look would look like for two factors that like for two factors that are are not correlatednot correlated??

What would its What would its correlation coefficientcorrelation coefficient be?be?

r=0.00r=0.00

Correlation ≠ CausationCorrelation ≠ Causation

ReviewReview

What is the What is the differencedifference between a between a populationpopulation and a and a samplesample??

How could one effectivelyHow could one effectively create create a a representative samplerepresentative sample??

What is the What is the difference difference between a between a positivepositive and and negative correlationnegative correlation??

What are some What are some implicationsimplications of a of a correlationcorrelation??

HomeworkHomework

Research Study Response #40: Research Study Response #40: “Obey At Any Cost?” (Pgs. 308-317)“Obey At Any Cost?” (Pgs. 308-317)