faculty claves ap psyc unit 1 history research perspectives resarch methods pp

8/12/2019 Faculty Claves AP Psyc Unit 1 History Research Perspectives Resarch Methods PP

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Psychology as a Science

In this discussion we will explore: limits of common sense

science - a method for understanding

methods of science

description

correlation experimentation

evaluating data with statistics

sources of error and bias in research


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How do we know things?

We Just Know It Intuition orCommon Sense

OR

Tried and True Science

Can we trust our intuition?


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Science vs. Common Sense

Why dont we rely on intuition

(common sense)?

1. Hindsight Biastendency to believe,after learning an outcome, that one

would have foreseen it. To find out something has happened, makes it

inevitableI Knew It All Along Phenomenon


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Why dont we rely on

intuition (common sense)? 2. Overconfidencewe tend to think

we know more than we do Humans are usually more confident than

correct.

Try these anagrams: WREAT

ETRYN

GRABE

OCHSA


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Why dont we rely on

intuition (common sense)?Water

Entry

Barge

Chaos

Once people know the target word,

hindsight makes the words obvious. Webelieve that we should have seen thesolution in a shorter period of time.


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Common sense and intuition often tellus about psychology

e.g., suppose a study tells us that separationweakens romantic attraction

common sense may tell us -out of sight, outof mind

or common sense may say the opposite -absence makes the heart grow fonder

Common sense can be inconsistent

and based on hindsight


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Science helps build explanations thatare consistent and predictive rather

than conflicting and postdictive(hindsight)

Science is based on

knowledge of facts developing theories

testing hypotheses

public and repeatable procedures


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Scientific Inquiry/Research

Facts are what need to be explained objective - viewable by others

based on direct observation

reasonable observers agree are true

Theory is a set of ideas that organizes facts

makes predictions about observations (new facts)

Hypothesis prediction about new facts (often implied by theory)

can be verified or falsified


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Scientific Inquiry/Research

As a check on their bias, psychologistsreport their findings with

Operational Definitions (of Concepts):a statement of the procedures used to

define research variables

Operational Definitions allow others toreplicate the study (repeating the essenceof the study to get similar results).


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Research Methods in

PsychologySetting - field vs. laboratory

Methods of data collection self-report vs. observational

Research plan or design

descriptive correlational

experimental


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Descriptive Research

Describes a set of facts

Doesnotlook for relationships

between facts Doesnotpredict what may influence

the facts

May or may not include numerical data

Example: measure the % of new studentsfrom out-of-state each year since 1980


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Descriptive Research

Types of descriptive research

1. Case Study

In-depth study of one individual

2. Naturalistic Observation

Recorded observation of people or animalsin their natural environmentfocus on aspecific behavior

3. Survey


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Surveys

Wording Effect - need to watch forbias, order of wording, too general

(attractiveness, intelligence)

Sampling

False Consensus Effecttendency to

overestimate others agreement with us Creates the need for a representative sample

of the population


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Surveys

Sampling Contd.

Populationall the cases in a group,

from which samples may be drawn for astudy (e.g. study on studying habitspopulation would be allstudents)

Random Samplesample in which everyperson in a group has equal chance ofparticipating


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Correlational Resarch

Collects a set of facts organized intotwo or more categories

measure parents disciplinary style measure childrens behavior

Examines the relationships between

2 or more categoriese.g., more democratic parents have

children who behave better


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Correlational Research

Correlation CANNOT prove causation Do democratic parents produce better

behaved children? Do better behaved children encourage

parents to be democratic?

May be an unmeasured commonfactor e.g., good neighborhoods produce

democratic adults and well behaved children


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Scatterplotsgraphed cluster ofdots, each of which represents the

values of two variables See pg. 27 for examples

Correlation Coefficientastatistical measure of relationship Statistical measure of the extent to which

two factors vary together, and thus of

how well either factor predicts the other.


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Direction of a Correlation

(slope of the points)

Positive Correlationas one variable

goes up, the other variable tends togo up (so as one goes down, the othergoes down)max. +1.00

NegativeCorrelationas onevariable goes up, the other tends togo down, the inverse is also truemin. -1.00

No Correlationcorrelation is 0.0


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Strength of Correlation

(amount of scatter)

The higher the correlation coefficient

is (without regard to sign) thestronger the correlation is.

The stronger the correlation is, thebetter one variable can predict theother.


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Correlations make visible relationshipsthat we might otherwise miss.

They also restrain our seeingrelationships that actually do not exist

illusory correlationsperception of a

relationship where none exists(e.g., superstitious beliefs)

Believelikely to notice and recall


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Perceiving Order

As humans we want to make sense of ourworld, so we look for meaningful

patterns.ProbRandom sequences often dont

look randomleads to illusory corr.

If someone flipped a coin six times, which ofthe following sequences of H and T would bemost likely?

HHHTTT HTTHTH HHHHHH


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A little note about correlation

CORRELATION

DOES NOT PROVECAUSATION!!


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Experiments

Direct way to test a hypothesis about acause-effectrelationship between

variables

One variable is controlled by theexperimenter e.g., democratic vs. authoritarian classroom

The other is observed and measured e.g., cooperative behavior among students


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Experimental Variables

Independent variable the controlledfactor in an experiment

what the experimenter manipulates hypothesized to cause an effect on anothervariable

Dependent variable the measuredfacts/data

hypothesized to be affected


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Independent Variable

Must have at least two levels categories - male vs. female

numeric - ages 10, 12, 14

Simplest is experimental vs. control experimental condition gets treatment

(e.g., gets the new drug) control condition does not

(e.g., gets the placebo)

(created when using a double-blind procedure)


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Experimental Design

Levels may differ between or withinpeople

Within-subject experiment - differentlevels of the independent variable areapplied to the same subject

Between-groups experiment - differentlevels of the independent variable areapplied to different groups of subjects


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Experimental Design

Random sample - every member of thepopulation being studied should have anequal chance of being selected for thestudy

Random assignment - every subject in thestudy should have an equal chance of

being placed in either the experimental orcontrol group

Randomization helps avoid false results


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Experimental Design

Validityextent to which a testmeasures or predicts what it is

supposed toInternalValiditycontrolled for

confounding variables (if randomassignment is violated, can destroy

internal validity)

ExternalValiditygeneralizability(if random sample is violated, can

destroy external validity)


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Sources of Bias

Observer-expectancy effect researcher has expectations that

influence measurements Subject-expectancy effect

subject knows design and tries toproduce expected result

Blinding minimize expectancy by removing

knowledge about experimental conditions


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Blinding

Single-blind study - when subjectsare kept uninformed as to the

treatment they are receiving

Double-blind study - when both

subjects and experimenter arekept uninformed about aspects ofthe study that could lead to

differential expectations


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Double Blind Procedures

Double Blind Procedures allow researchersto check for a treatments actual effects

apart from the placebo effect- experimental results caused by

expectations alone; such as a research

participants enthusiasm for it or thehealing power of belief


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Sources of Bias

Confounding Variables -

Any variable besides the

independent variable that affectsthe dependent variable in one groupbut not the other.

(e.g., placebo takes a study skillsseminar, non random assignment)


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Research Settings

Laboratory a setting designed for research

provide uniform conditions for all subjects

permits elimination of irrelevant factors

may seem artificial

Field research behavior observed in real-world setting

poor control over conditions

measures may be more representative of

reality


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Data-Collection Methods

Self-report - procedures in whichpeople rate or describe their own

behavior or mental state questionnaires

rating scales

on a scale from 1 to 7 rate your opinion of judgements about perceptions

on a scale from 1 to 100 how hot is ...


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Observational methods - researchersdirectly observe and record behavior

rather than relying on subjectdescriptions naturalistic observation - researcher records

behavior as it occurs naturally tests - researcher presents stimuli or

problems and records responses


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Cross-Sectional Studiesstudy inwhich subjects of different ages are

compared at a given time

Longitudinal Studiesstudy in which

subjects are followed and periodicallyreassessed over a period of time


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Meta-Analysiscombine andanalyze data from many studies; it

determines how much of thevariance in scores across allstudies can be explained by a

particular variable

faculty claves ap psyc unit 1 history research perspectives resarch methods pp

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