PSYCHOLOGY AND ITS METHODS

Psychology & the scientific methodFrom Questions to Results

Psychologists use the scientific method to conduct their research. The scientific method is a standardized way of making observations, gathering data, forming theories, testing predictions, and interpreting results.

Researchers make observations in order to describe and measure behavior. After observing certain events repeatedly, researchers come up with a theory that explains these observations. A theory is an explanation that organizes separate pieces of information in a coherent way. Researchers generally develop a theory only after they have collected a lot of evidence and made sure their research results can be reproduced by others.

Key Info

The scientific method is a way to ask and answer scientific questions by making observations and doing experiments.The steps of the scientific method are to:Ask a QuestionDo Background ResearchConstruct a HypothesisTest Your Hypothesis by Doing an ExperimentAnalyze Your Data and Draw a ConclusionCommunicate Your ResultsIt is important for your experiment to be a fair test. A "fair test" occurs when you change only one factor (variable) and keep all other conditions the same.1

Research questions

Tips for Writing Research Questions

Be as specific as possible. In some cases, you may make two or more research questions to cover a complex topic.

Be flexible. For example, if you are studying the effects of sleep on reflexes, you might formulate the following research question: What are the effects of sleep on reflexes? A similar question might be: Does sleep have an effect on reflexes? OR Is maximum reflex efficiency achieved after eight hours of sleep?

Remember: The goal of your research is to find the answer to the research question. Make sure that the question reflects your goals in its words and phrasing.

Use this tutorial if you are writing research questions for a qualitative design.Tips for Writing Hypotheses

When you state your hypotheses, be sure that the content of the hypothesis matches the experimental procedure. What you write should be the best estimation of the outcome of the lab procedure. Along with the hypothesis, you should write several sentences which explain the scientific reasoning that led you to that hypothesis.

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2. Theory3. How might you test it?3

Any other questions anyone wants to add? And anyone else want to form a hypothesis?5

Reflect: What are your questions?

Becoming a Psychological DetectiveIn evaluating causal or research claims, we should ask the following questions: What is the statement or claim, and who is making it? Is the statement or claim based on scientific observations? What do statistics reveal? Are there plausible alternative explanations for the statement or claim?

Psychology is Science

Psychologists and other social scientists regularly propose explanations for human behavior. On a more informal level, people make judgments about the intentions, motivations and actions of others on a daily basis. While the everyday judgments we make about human behavior are subjective and anecdotal, researchers use the scientific method to study psychology in an objective and systematic way. The results of these studies are often reported in popular media, which leads many to wonder just how or why researchers arrived at the conclusions they did.

In order to truly understand how psychologists and other researchers reach these conclusions, you need to know more about the research process that is used to study psychology and the basic steps that are utilized when conducting any type of psychological research. By knowing the steps of the scientific method, you can better understand the process researchers go through to arrive at conclusions about human behavior.

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Goals of Psychology

The study of psychology has five basic goals:

1. Describe

The first goal is to observe behavior and describe, often in minute detail, what was observed as objectively as possible

2. Explain

While descriptions come from observable data, psychologists must go beyond what is obvious and explain their observations. In other words, why did the subject do what he or she did?

3. Predict

Once we know what happens, and why it happens, we can begin to speculate what will happen in the future. Theres an old saying, which very often holds true: the best predictor of future behavior is past behavior.

4. Control

Once we know what happens, why it happens and what is likely to happen in the future, we can excerpt control over it. In other words, if we know you choose abusive partners because your father was abusive, we can assume you will choose another abusive partner, and can therefore intervene to change this negative behavior.

5. Improve

Not only do psychologists attempt to control behavior, they want to do so in a positive manner, they want to improve a persons life, not make it worse. This is not always the case, but it should always be the intention.

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RESEARCH METHODS

Chapter Summary:Making ObservationsDefining the QuestionSystematically Collecting DataDefining the SampleAssessing External ValidityMonitoring Demand CharacteristicsWorking with DataDescriptive StatisticsInferential StatisticsObservational StudiesAmbiguity about CausationEstablishing Cause and Effect: The Power of ExperimentsExperimental Groups versus Control GroupsRandom AssignmentWithin-Subject ComparisonsInternal ValidityBeyond the Single ExperimentResearch EthicsThe Power of ScienceSome Final Thoughts: Methodological EclecticismSummary

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The Scientific method

Key Terms to Know

Hypothesis: An educated guess about the possible relationship between two or more variables.

Variable: A factor or element that can change in observable and measurable ways.

Operational Definition: A full description of exactly how variables are defined, how they will be manipulated, and how they will be measured.

Before a researcher can begin, they must choose a topic to study. Once an area of interest has been chosen, the researchers must then conduct a thorough review of the existing literature on the subject. This review will provide valuable information about what has already been learned about the topic and what questions remain to be answered.

A literature review might involve looking at a considerable amount of written material from both books and academic journals dating back decades. The relevant information collected by the researcher will be presented in the introduction section of the final published study results. This background material will also help the researcher with the first major step in conducting a psychology study formulating a hypothesis.

Step 1 Forming a Testable HypothesisStep 2 Devise a Study and Collect DataStep 3 Examine Data and Reach ConclusionsStep 4 Report the Findings of the Study13

Making Observations in The Research process

A comprehensive flow chart of the research process

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What is a variable?Variable: Any characteristic whose values can changei.e. something that can vary

Defining the QuestionObserve the World!The basis of research, is coming up with a question and making a prediction about the answer that you can test (hypothesis)Your Hypothesis is Your Prediction

HYPOTHESIS & VARIABLESYour Hypothesis is Your Prediction ABOUT THE RELATIONSHIP OF VARIABLES

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From Questions to testable Hypotheses

Testable hypothesis: a prediction that has beeen formulated specifically enough so that it is clear what observations would confirm the prediction and what observations would challenge it18

Operational Definitions

How you operationalize the variables will tell us if the study is valid and reliable.

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.

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Defining your variables

Collecting Data

Defining the sample

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External Validity

Can we generalize?Population Validity: Generalizability to other peopleEcological Validity: Generalizability to other settings

External Validity

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Monitoring demand characteristicsDemand CharacteristicsDouble-blind Design

Threat to Construct: Demand Characteristics

Keep subjects blind and experimenters so they dont know what is expected from them

Double blind studyRandom assignment of test subjects to the experimental and control groups is a critical part of any double-blind research design. The key that identifies the subjects and which group they belonged to is kept by a third party, and is not revealed to the researchers until the study is over.

Working with Data

Psychological ResearchExperimental researchDescriptive researchNaturalistic Observationmeasure and record behavior of participantsSurveysused to determine opinions, attitudes, feelings or behaviors related to a specific issueCase studiesintensive study of a particular case, patient or situationCorrelational researchIdentifies relationships between variablesStatistical analysisNo cause and effect only relationshipsBiological researchStudies brain and nervous systemIdentifies cause, description and predictionShares advantages/disadvantages of other three typesSeveral methods of study (see text pp. 37-38)

Measures of Central Tendency

Mean: Average of dataMedian: 50th percentile, half above, half belowMode: most frequently occurring scoreUsually the mean is the best measure, but with very extreme scores or skewed data, the median is most accurate

Copyright Prentice Hall 20071-31Research Methods in PsychologyCorrelational research tells whether the values of two variables are related.

The Correlation CoefficientLooking at the relationship between X (predictor) and Y (criterion)While there isnt an IV/DV, X is often consider the X the IV and the Y the DVRange: -1.0 1.0

Correlation is about Association not CausationCorrelation coefficient (r):summarizes degree of association between X and Y variablesr ranges from -1.0 to + 1.0Close to zero is weaker, close to -1 or +1 is strongerPositive: One goes up, the other does, Negative: Inverse

Degree of association between two or more variablesX = Predictor (IV)Y = Criterion (DV)

Correlations GraphicallyCloser the points to the line, the stronger the correlationVariability (spread) is equal on X and Y when there is a 0 correlation.

Inferential Statistics

Tests of Relationships and Prediction

Observational StudiesOne common observational study is about the possible effect of a treatment on subjects, where the assignment of subjects into a treated group versus a control group is outside the control of the investigator.

Establishing Cause and Effect: The Power of Experiments

Variables in Experimental Research

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Types of Research

True versus Quasi experimental design

RANDOM ASSIGNMENT DISTINGUISHES TRUE V. QUASI-EXPERIMENTAL RESEARCH

Mediating and Moderating VariablesMediator Variable: Is responsible for the observed relationship between IV and DVModerator Variable: Affects strength of relationship between IV and DV

EXAMPLE OF MEDIATOR VARIABLE

Random Assignment versus Random SelectionRandom Selection: How you got the subjects from the populationRandom Assignment: Once you have the subjects, how do you assign them to groups

Between Groups Vs. Within Subjects

Internal validityInternal Validity: Can we determine there is a causal relationship between IV and DV?External: Can the relationship be generalized?

Threats to Internal Validity

Effect SizeThe practical or clinical significance of the resultsTypes of Effect Size:Cohens dEta squaredAlso used in meta-analysis. Different studies converted to common metric so results can be compared

Research EthicsHuman participantsInformed consentDeceptionConfidentiality/anonymitySpecial issues for studentsNon-human participantsEthical issues related to psychotherapy

Informed consent

DebriefingEnd of study, researcher explains the purpose and undoes manipulations

Debriefing is an exchange of dialogue that occurs between a researcher and a participant after data collection. Researchers give a brief explanation of the purpose of the study, its logic, and its implications. They give their contact information in case the participants have questions or concerns about the experiment. The participants are given citations of one or two articles for more information about the research. Any manipulations performed and the rationale for using them is also explained during debriefing. Participants are given a chance to ask questions about the experiment. The researchers use simple language when conducting debriefing so that the participants do not feel like they are being buried with uninformative jargon (Instructions for preparing, 2007).

The purpose of debriefing is to make sure that the participants are restored to pre-experimental levels. They can be emotionally affected by research involving stress, manipulations of self-esteem, or strong emotional arousal. By explaining the research and manipulations used, debriefing attempts to make sure that the participants are as well-off after participation as they were before they participated in the experiment (What is debriefing?).

Researchers can choose to debrief immediately after participation or they can arrange a later time for group debriefing. However, if data collection involved manipulations of failure, strong humiliation, strong deception, or reduction in self-esteem, researchers should give each participant at least partial debriefing immediately so that participants are not harmed (What is debriefing? ). They researchers should tell participants where they can talk to a counselor if they feel it is necessary and that the participants are free to withdraw their data if they like. Researchers should do debriefing orally in these cases. However, in other cases, debriefing can be in a written form. Participants can be handed a sheet of paper with the debriefing information (Instructions for preparing, 2007).

Debriefing Session:

References:

Instructions for preparing the debriefing form for the psyc 100 subject pool application. (2007, October 22). Retrieved from http://www.queensu.ca/psychology/Research/Subject-Pool/debriefingform.doc

What is debriefing? (n.d.). Retrieved from http://www.depauw.edu/admin/acadaffairs/researchProtocols/IRB/Debriefing.html49

Key Terms