Research Methods (8-10%)

https://www.youtube.com/watch?v=hFV71QPvX2I

Applied V. Basic Research• Applied Research

has clear, practical applications.

• YOU CAN USE IT!!!

• Basic Research explores questions that you may be curious about, but not intended to be immediately used.

Research on therapies for drug addicts has a clear purpose.

Studying how kissing changes when you get older is interesting…but that’s about it.

Why do we have to learn this stuff?

Psychology is first and foremost a science.

Thus it is based in research.Before we delve into how to do research, you should be aware of three hurdles that tend to skew our logic.

Hindsight Bias

• The tendency to believe, after learning the outcome, that you knew it all along.

Monday Morning Quarterbacking!!!

After the Chris Brown/Rihanna incident….lots of people said they knew Chris Brown was a violent guy… Did they really?

Overconfidence

• We tend to think we know more than we do.

• 82% of U.S. drivers consider themselves to be in the top 30% of their group in terms of safety.

• 81% of new business owners felt they had an excellent chance of their businesses succeeding. When asked about the success of their peers, the answer was only 39%. (Now that's overconfidence!!!)

The Barnum Effect

• It is the tendency for people to accept very general or vague characterizations of themselves and take them to be accurate.– Examples:

• Horoscopes • Fortunes• Year of ____ “place mat”

Terminology

Theory

• An explanation using a set of principles that organizes / predicts behaviors or events.

Hypothesis

• Expresses a relationship between two variables.

• A variable is anything that can vary among participants in a study.

• Participating in class leads to better grades than not participating.

The Need for Psychological Science

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.

Psychology’s Research Strategies

• Psychology’s research strategies include descriptive, correlational and experimental

• Pg. 40-study

Descriptive

Case Study Psychologists

study one or more individuals in great depth in the hope of revealing things true of us all

Is language uniquely human?

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 Plus 8. Really interesting, but what does it tell us about families in general?

Descriptive

Survey technique for ascertaining the self-reported

attitudes , opinions or behaviors of people usually by questioning a representative, random

sample of people Random Sample

a sample that fairly represents a population because each member has an equal chance of participating

Ex- survey calls or individuals outside of stores

Survey Method

•Most common type of study in psychology

•Measures correlation

•Cheap and fast

•Need a good random sample

•Low-response rate

Descriptive Naturalistic Observation

observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation

Ex- animals, children in their home or schools

Correlation Correlation Coefficient

a statistical measure of the extent to which two factors vary together, and thus how well either factor predicts the other.

Ex-knowing how much aptitude test score correlate with school success tells us how well the scores predict school success

Correlation coefficient

Indicates directionof relationship

(positive or negative)

Indicates strengthof relationship(0.00 to 1.00)

r = +.37

Correlation

Scatterplot a graphed cluster of dots, each of which represents

the values of two variables the slope of the points suggests the direction of the

relationship p.31 the amount of scatter suggests the strength of the

correlation little scatter indicates high correlation

also called a scattergram or scatter diagram

Correlation

Perfect positivecorrelation (+1.00)

No relationship (0.00) Perfect negativecorrelation (-1.00)

Scatterplots, showing patterns of correlations

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.

Correlation

Three Possible Cause-Effect Relationships(1)

Low self-esteemDepression

(2)Depression

Low self-esteem

Low self-esteem

Depression

(3)Distressing events

or biologicalpredisposition

could cause

could cause

could cause

or

or

and

Experimentation

Experiment an investigator manipulates one or more

factors (independent variables) to observe their effect on some behavior or mental process (the dependent variable)

by random assignment of participants the experiment controls other relevant factors

Sampling• Identify the

population you want to study.

• The sample must be representative of the population you want to study.

• GET A RANDOM SAMPLE

Experimentation

Placebo an inert substance or condition that may be

administered instead of a presumed active agent, such as a drug, to see if it triggers the effects believed to characterize the active agent

Double-blind Procedure both the research participants and the research staff

are ignorant (blind) about whether the research participants have received the treatment or a placebo

commonly used in drug-evaluation studies

Random Assignment

• Once you have a random sample, randomly assigning them into two groups helps control for confounding variables.

• Experimental Group v. Control Group.

Beware ofConfounding Variables

If I wanted to prove that smoking causes heart issues, what are some confounding variables?

• The object of an experiment is to prove that A causes B.

• A confounding variable is anything that could cause change in B, that is not A.

Lifestyle and family medical history may also effect the heart.

Operational Definitions• A statement of procedures

used to define research variables.

• 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?

Hawthorne Effect

• But even the control group may experience changes.

• Just the fact that you know you are in an experiment can cause change.

• http://psychology.about.com/od/hindex/g/def_hawthorn.htm

Whether the lights were brighter or dimmer, production went up in the Hawthorne electric plant.

Experimentation

Statistics• Once data is gathered

we must organize, summarize and make inferences from it using statistics.

• Recording the results from our studies.

• Must use a common language so we all know what we are talking about.

Statistical Reasoning

Mode the most frequently occurring score in a distribution

Mean the arithmetic average of a distribution obtained by adding the scores and then dividing by the

number of scores Median

the middle score in a distribution half the scores are above it and half are below it

Normal Distribution

• In a normal distribution, the mean, median and mode are all the same.

Distributions

• Outliers skew distributions.

• If group has one high score, the curve has a positive skew (contains more low scores)

• If a group has a low outlier, the curve has a negative skew (contains more high scores)

Statistical Reasoning

Range the difference between the highest and lowest scores

in a distribution Standard Deviation

a computed measure of how much scores vary around the mean

Statistical Significance a statistical statement of how likely it is that an

obtained result occurred by chance

Other measures of variability

• Range: distance from highest to lowest scores.

• Standard Deviation: the variance of scores around the mean.

• The higher the variance or SD, the more spread out the distribution is.

Lebron and Wade may both score 30 ppg (same mean).But their SDs are very different.

Ethics in Research

Animal Research• Clear purpose

– b/c human physiology resembles various animals (esp. mammals)

– Some experiments are not permitted on humans

• Treated in a humane way

• Acquire animals legally

• Least amount of suffering possible.

Rats, mice, rabbits and birds are the types of animals often used in psych researech

Ethics Human Research

• No Coercion- must be voluntary

• Allow them to withdraw @ any time

• Informed consent

• Protect from harm & discomfort

• Must debrief • Protect confidentially

MILGRAM OBEDIENCE ExperimentEthical or unethical? pg. 706

• Stanley Milgram –Social psychologist.

• Studies about social interaction and obedience

• Discussion about obedience?

• 1. Now that you know about ethical guidelines for conducting human research, while watching the video, describe 3 ethical guidelines that would be violated if this experiment was conducted today.

• 2. Discuss and explain how you would have responded as a subject in the experiment? (giving the “electrical shocks” and as the individual that “received” the electrical shocks

Zimbardo Prison experiment

• Page 700Read

https://www.youtube.com/watch?v=1jdOoxnr7AI

• Also Milgram obedience experiment pg. 706

Normal Distribution

Scores

• A unit that measures the distance of one score from the mean.

• A positive z score means a number above the mean.

• A negative z score means a number below the mean.

Statistical Reasoning

A Skewed Distribution

15 20 25 30 35 40 45 50 90 475 710

70

Mode Median Mean

One Family Income per family in thousands of dollars