RESEARCH METHODS

Goals of Psychology Describe Explain Predict Control behavior and mental processes

Why is Research Important?

Research and Research Methodology Method of asking questions then drawing logical supported conclusions Researchers need to be able to determine if conclusions are reasonable or not (critical thinking).

Scientific Method Technique using tools such as observation, experimentation, and statistical analysis to learn about the world Through its use, psychology is thereby considered a science.

Steps to the Scientific Method Formulate testable questions –Develop hypotheses Design study to collect data –Experimental –Descriptive Analyze data to arrive at conclusions –Use of statistical procedures –Use of meta-analysis Report results –Publication –Replication

Theory Tentative explanation for observed findings Results from accumulation of findings of individual studies Tool for explaining observed behavior Reflects self-correcting nature of scientific method. Good way to think about a Theory: Prosecuting Attorney presents their theory backed up by evidence to the jury.

What are the Odds of Each?

1 in 2,598,960

What are the Odds of Each? 1 in 2,598,960

Common Sense Conclusions based solely on personal experience and sensible logic Can lead to incorrect conclusions

Did you know… It is nearly impossible to fold a regular sheet of paper in half more than 7 times. Go ahead and try! Mythbusters pulled it off with a piece of paper as big as an airplane hanger and a steam roller.Mythbusters

Science vs. Common Sense Science helps build explanations that are consistent and predictive rather than conflicting and describing the past (hindsight) Science is based on –knowledge of facts –developing theories –testing hypotheses –public and repeatable procedures

Hindsight Bias The Tendency to exaggerate one’s ability to have foreseen how something would turn out after learning the outcome. The “I knew it all along” phenomenon. Week before the 1985 Super Bowl, 81% of Dr. Brigham’s students predicted the Miami Dolphins would win. 40% said the Dolphins would win by 10 or more points. A week after San Fransisco 49ers decisive victory, he asked the group who picked the 49ers. 58% said they picked the 49ers NO ONE remembered saying the Dolphins would win by at least 10 points.

Overconfidence Tendency to overestimate the accuracy of our current knowledge We are more confident than we are correct. “Man will never reach the moon, regardless of all future scientific advances.” - Lee DeForest, inventor of vacuum tube, 1957 “Nuclear powered vacuum cleaners will probably be a reality within 10 years.” - Alex Lewyt, manufacturer of vacuum cleaners, 1955 “Reagan doesn’t have the presidential look.” - United Artist Executive in turning Reagan down for the starring role in The Best Man, 1964.

Confirmation Bias Our tendency to search for information that confirms our preconceptions. Try this card trick: This works because we only look for our chosen card confirming Simeon’s mental telepathy and ignore the fact that second set of cards is in fact, an entirely new set! NONE of the cards in the new set is the same as the old one so of course the card you picked is missing.

DAILY DOUBLE

QUESTION What is the difference between Common Sense and Science? ANSWER: Common sense relies on the past and may be wrong. Science uses facts to provide consistent predictions

BOREDOM BUSTER! Common Sense tells us squirrels are harmless… OR ARE THEY? RUNNING OF THE SQUIRRELS

Observation and Bias

Observation Gathering of information by simply watching subjects Can lead to bias

Bias Situation in which a factor unfairly increases the likelihood of a researcher reaching a particular conclusion Bias should be minimized as much as possible in research

Researcher Bias The tendency to notice evidence which supports one particular point of view or hypothesis Objectivity tends to reduce bias.

Participant Bias Tendency of research subjects to respond in certain ways because they know they are being observed The subjects might try to behave in ways they believe the researcher wants them to behave Can be reduced by naturalistic observation

Critical Thinking Thinking that does not blindly accept arguments or conclusions but questions their validity

Research Strategies

Descriptive—strategies for observing and describing behavior –Correlational methods –Naturalistic observation –Case studies –Surveys Experimental—strategies for inferring cause and effect relationships among variables

Descriptive Study Describes a set of facts Does not look for relationships between facts Does not predict what may influence the facts May or may not include numerical data Example: measure the percentage of new students from out-of-state each year since 1980

Naturalistic Observation Method of observation where subjects are observed in their “natural” environment Subjects are not aware they are being watched Could use hidden cameras or two way mirrors

Case Study In depth study of one individual with the hopes of determining universal principles This technique is very open to bias Difficulty of applying data from one person to everyone Generally used to investigate rare, unusual, or extreme conditions

Survey Method Research method that relies on self- reports; uses surveys, questionnaires, interviews. Usually a very efficient and inexpensive method Have to watch out what we take from polling information: Also, people lie in surveys: /post/lying-to-pollsters-bad-vote/ /post/lying-to-pollsters-bad-vote/

SamplingTerms Population—large (potentially infinite) group represented by the sample. Findings are generalized to this group. Sample—selected segment of the population Representative sample—closely parallels the population on relevant characteristics Random selection—every member of larger group has equal chance of being selected for the study sample

Population The total large group being studied from which a sample is drawn for a study

Random Sample A sample that represents a population fairly: –Each member of the population has an equal chance of being included. –If a sample is not random it is said to be biased.

DAILY DOUBLE

QUESTION Explain the difference between a random sample and a representative sample. ANSWER: Representative sample—closely parallels the population on relevant characteristics Random selection—every member of larger group has equal change of being selected for the study sample

Longitudinal and Cross-Sectional Studies

Developmental Psychologists Psychologists who study how individuals change throughout their lifetime

Longitudinal Study Developmental study where researchers study the same group of individuals for many years Can be very expensive and difficult to conduct

Cross-Sectional Study Developmental study where researchers simultaneously study a number of subjects from different age groups and then compare the results Cheaper, easier than longitudinal studies, but group differences may be due to factors other than development.

Longitudinal/Cross Sectional Study

Correlational Study Collects a set of facts organized into two or more categories –measure parents’ disciplinary style –measure children’s behavior Examine the relationship between categories Correlation reveals relationships among facts –e.g., more democratic parents have children who behave better

Correlational Study Important NOT to imply a cause and effect relationship between the variables Correlational study does not determine why the two variables are related--just that they are related. Correlational studies are helpful in making predictions.

Correlational Study Correlation CANNOT prove causation –Do democratic parents produce better behaved children? –Do better behaved children encourage parents to be democratic? May be an unmeasured common factor –e.g., good neighborhoods produce democratic adults and well-behaved children

Correlation & Causation There is a strong +.90 correlation in shoe size and IQ. Does this mean that a large shoe size is the cause for higher intelligence? What else could explain this? YOUR FEET GROW AS YOU GET OLDER & WISER

Coefficient of Correlation Numerical indication of magnitude and direction of the relationship between two variables –Positive correlation—two variables vary systematically in the SAME direction –Negative correlation—two variables vary systematically in OPPOSITE directions

How to Read a Correlation

Positive Correlation As the value of one variable increases (or decreases) so does the value of the other variable. A perfect positive correlation is The closer the correlation is to +1.0, the stronger the relationship.

Negative Correlation As the value of one variable increases, the value of the other variable decreases. A perfect negative correlation is The closer the correlation is to -1.0, the stronger the relationship.

Zero Correlation There is no relationship whatsoever between the two variables.

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