Scientific ResearchAssumes that events are governed by

some lawful order

Goals of the Scientific Enterprise

1. Measurement and description: the first goal of psychology is to develop measurement techniques that make it possible to describe behavior clearly and precisely.

2. Understanding and prediction: To evaluate their understanding, scientists make and test predictions called hypotheses.

Definitions

A hypothesis is a tentative statement about the relationship between two or more variables.

Variables are any measurable conditions, events characteristics or behaviors that are controlled or observed in a study.

Steps in a Scientific Investigation5 systematic steps to consider

1. Step 1: Formulate a testable hypothesis:

Normally expressed as predictions, they spell out how changes in one variable will be related to changes in another variable.

To be testable, scientific hypotheses must be precisely formulated and variable clearly defined in operational definitions; describes the actions or operations that will be used to measure or control a variable.

Step 2: Select the Research Method and Design the Study

The type of research method chosen depends on the type of question under study. The researcher might choose a case study, experiment, naturalistic observation, survey or others, each with specific advantages and disadvantages.

Once the method is determined, it is necessary to then chose the participants or subjects, whose behavior is systematically observed.

An Observational Study

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Step 3: Collect the data

Researchers use a variety of data collection techniques, procedures for making empirical observations and measurements.

Examples are direct observation questionnaires, interviews, psychological tests, physiological recordings and examination of archival records.

Analyzing Data

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Step 4: Analyze the Data and Draw Conclusions

Collected data and observations are turned into numerical values which then become “raw data” for the study.

Researchers then use statistics to analyze their data and to decide whether their hypotheses have been supported.

It is important to stress that all factors must be considered before making inferences about

conclusions.

Step 5: Report the Findings

Scientific progress can be achieved if researchers share their findings with one another and the general public.

The FINAL step is to write up a concise summary of the study and it findings. Often the work is presented at a scientific meeting and submitted to a scholarly journal for publication.

Once published, it is evaluated by other researchers for flaws

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Advantages of the Scientific Approach

• Clarity and Precision- requires that people specify exactly what they are talking about when they formulate hypotheses which enhances communication about important ideas.

• Intolerance of Error- Scientists are skeptical and trained to question data and look at empirical tests, documentation and objective data to convince them of new ideas.

Research MethodsConsist of various approaches to the

observation, measurement, manipulation, and control of variable in empirical studies.

No single research method is ideal for all purposes and situations.

We will look at the two major types: experimental research methods and

descriptive/correlational research methods.

Experimental MethodAn experiment is a research method

in which the investigator manipulates a variable under

controlled conditions and observes whether any change occur in a second variable as a result.

DisadvantagesInformation obtained in an experimental situation or

laboratory may not apply to real life

AdvantagesGreatest potential for identifying cause and effect relationships with less error and bias than either survey or case study

Independent and Dependent Variables

An independent variable is a condition or event that an experimenter varies in order to see its impact on another variable.

The independent variable is thought to be independent because it is free to be varied by the researchers and it is hypothesized to have some effect on the dependent variable.

The dependent variable is the variable that is thought to be affected by manipulation of the independent variable.

The dependent variable is thought to depend on the manipulations of the independent variable.

Experimental and Control Groups

The experimental group consists of the subjects who receive some special treatment in regard to the independent variable.

The control group consists of similar subjects who do NOT receive the special treatment given to the experimental group.

Extraneous and Confounding Variables

Extraneous variables are other variables that might cloud the researcher’s ability to draw causal conclusions about how the independent variable affects the dependent variable.

Confounding variables occur when two variables are linked together in a way that makes it difficult to sort out their specific effects.

Random AssignmentIt is important to insure that subjects are assigned to either the control or experimental group in a

manner that is RANDOM and an equal chance of assignment

to either group or condition in the study is possible.

When assigned to groups randomly, there is a better chance of the groups being

similar.

Experimental BiasExperimental Bias: : Researchers expectations influence the

results of the experiment or study. Can include non-verbal clues to subjects like facial expressions and body language.

Double-Blind StudyDouble-Blind Study: Neither the : Neither the subjects nor the researchers subjects nor the researchers know which group is receiving know which group is receiving the treatment. Important to the treatment. Important to control for self-fulfilling control for self-fulfilling

propheciesprophecies

Experimental Method

Disadvantages1.Information obtained in an

experimental situation or laboratory may not apply to

real life2.Sometimes, this method cannot be used to answer the question

at hand.Advantages

Greatest potential for identifying cause and effect relationships with less error and bias than either survey

or case study

Control Group/PlaceboPlacebo Effect: Participants

expectations cause them to experience a change even

though treatment is ineffectual. Can be used in

a study to determine a cause and effect relationship.

Descriptive/Correlational Research: Broaden the scope of phenomena that

psychologists are able to study

Naturalistic Observation: The careful observation of behavior without intervening directly with the subjects. It is called naturalistic because behavior is allowed to unfold naturally without inference in the it natural environment.

• The advantage of this method is that it is less artificial than in experiments.

• A disadvantage is that researchers often have trouble making their observation unobtrusively so they don’t affect their participants behavior.

Case Study:In-depth study of single person

Disadvantages1.Researcher may have personal

beliefs and bias2.It may be a self-fulfilling

prophecy- having a strong belief about a behavior and then

acting, usually unknowingly, to

fulfill or carry out the behavior

AdvantagesDetailed information allows

greater understanding of a

particular person’s life

Survey Method

There are three types of Surveys:1.Questionnaires

2.Interview3.Standardized Tests

A survey is a way of obtaining information by asking many individuals

to answer a fixed set of questions

An Example: What percent of the population is gay? Three different surveys reported three different answers: 2.3%,

10%, 22%

Disadvantages of Surveys1.How questions are worded-questions can be written to bias the answer

2.Who asks the question- sex or race of the questioner can also affect how people answer the question. People give desirable rather than honest answers.Advantages of Surveys

Quickly gather a large amount of information from a large

amount of people

Code of Ethics •Deception•Animal Research•Ethical Guidelines•Debriefing•Privacy•Approval from host institutions•Voluntary and Informed Consent•Safety (physical and emotional)