Chapter 2 – Introduction to the Methods of Science
Chapter Outline
Naturalistic Observation
The Correlational Approach
The Experimental Method
Definitions in the Experimental Method
Causation
Exploratory Research
Logic and Inference: The Detective Work of Science
Validity
Propositional Logic
Scientific Observation: The Raw Data of Science
Evaluating Scientific Research
Communication in Science
Chapter Overview
Science is an extension of how we go about exploring the world. Naturalistic observation involves observing and describing what occurs. In the correlational approach, the scientist examines the association between variables; this method does not imply causality. However, the experimental method allows the testing of cause and effect relationships by manipulating the independent variable and measuring its effect on the dependent variable. Hypotheses are tested using experimental and control groups; the variables that are manipulated and measured should be operationally defined. Scientists may also engage in exploratory research.
In testing hypotheses, science must rely on logic and inference. There is particular interest in ensuring the validity of research; internal and external validity must be present in the experiment. Logic, through inductive and deductive reasoning, plays an important role in ruling out alternative explanations. Popper’s and Kuhn’s views of science have shaped how scientists go about asking and answering questions.
It is important to communicate to the scientific community the results of research that are accurate, capable of being replicated, and relevant to others.
Chapter Objectives
1.Integrate these three important aspects of science: (1) idea, (2) experience, and (3) reorganization.
2.What are the strengths and weaknesses of naturalistic observation? Give an example of this type of study.
3.When would you use the correlational approach? What conclusion is justified? What is a positive correlation? How does it differ from a negative correlation?
4.Describe the experimental method. Why is it the most powerful design? Discuss the importance of operational definitions of variables.
5.Differentiate between the independent and dependent variables.
6.What is a confounding variable and how does it affect interpretation of the findings?
7.Explain causation in terms of necessary and sufficient conditions.
8.What is the balance between internal and external validity in research?
9.A scientist relies on both deductive and inductive logic in science. Distinguish between these reasoning methods and evaluate when they are used in the scientific process.
10.How does modus tollens apply to testing scientific theories?
11.How are scientists influenced by paradigms? Give examples of paradigm shifts.
12.According to the text, what are the four ways to ensure the high quality of research?
13.Aristotle emphasized scientific inquiry and argument. How do they relate to communication of science?
Teaching Points
The chapter describes other methods developed to answer specific questions (e.g., single-case approaches, qualitative methods). In fact, there are several single-case studies that many students might be familiar with and are worth reminding them of. For instance, most introductory psychology courses discuss Phineas Gage as an illustration of the case study ( In addition, you might suggest that focus groups, commonly used in marketing research, are a type of qualitative method. Perhaps some of your students have participated in focus groups sponsored by your institution.
The premise of naturalistic observation is very familiar to students. Many of them have engaged in watching others in parks, airports, and the student union. One of the famous examples of naturalistic observation is Jane Goodall’s work with chimpanzees. Check out her website for more information. One of the challenges in naturalistic observation is being unobtrusive. Researches often come up with ingenious ways to deal with this issue. For instance Irenäus Eibl-Eibesfeldt and Hans Hass studied facial expressions using a film camera that would actually record events that were occurring to the side of the camera, not in front were the “lens” appeared to be.
A problem area for students is in the use of the words positive and negative. It is important to remind them that positive and negative, as in correlations, describe the direction of the relationship, not any type of value statement as in a good or bad correlation.
Students often have great difficulty distinguishing between the independent and the dependent variables as well as formulating operational definitions. One helpful trick is to use “ICED” where the Independent variable is Cause and the Effect is the Dependent variable. Offer lots of practice identifying variables and creating operational definitions. A good starting place is to give students hypotheses to test:
- It is harder to concentrate when there is loud music playing.
- People feel sad in rooms painted blue.
- Depression impairs memory.
- People recall more pleasant than unpleasant experiences when happy.
It is useful to have students know the pros and cons of each research method that is described. For example, the naturalistic observation method is very good for studying natural behavior, but the researcher has no control over what happens. Control is a strength of the experimental method, but control can make conditions artificial and hence unrealistic.
Teaching Activities
Role of the Scientist
The scientist plays a different role in each of the methods described in the chapter. Use Handout 2-1 to help students identify those roles as well as to better understand the methods.
Doing Naturalistic Observation
One effective way to illustrate the challenge inherent in naturalistic observation is to assign students the task of observing behavior in a public setting such as a cafeteria or park. Inform them that they must simply describe what they observed. Of course, they should operationally define the variables they are observing. Many students will initially interpret and attribute the observed behavior to some cause. Moreover, having students make these observations in pairs allows for a discussion of interrater reliability and may augment this activity.
Correlation in the Popular Media
One of the most often-made mistakes regarding correlation is describing the relationship in terms of causality. Scour the popular media for articles that use the term “correlation.” Have students examine these articles for direct or indirect references to causation.
Testing Old Wives’ Tales using the Experimental Method
An effective way to help students better understand the experimental method is to test common sayings. Ask students to select a saying and then to develop an experiment to test its validity. Part of the task is to identify the independent and dependent variables, create operational definitions of variables, and to indicate the experimental and control groups.
Test a Memory Drug
As a class, design a simple experiment to test a fictional memory drug. Ask the students to identify the experimental group, control group, independent variable, dependent variable, placebo, and means of assigning subjects to groups.
Infomercials and the Scientific Method
Record an infomercial and show it to your class. Alternatively, visit a website that describes some of the products pitched on infomercials (see below). Have students evaluate the claims. Discuss how they would go about testing the claims from a scientific approach.
Philosophy of Science: Sir Karl Popper (Falsification Approach)
One helpful activity to teach falsification is to claim that photographs move when we don’t look at them. The claim continues that people and objects return back to their original location as we observe the picture. To emphasize the point, ask students to find a photograph in the textbook and then close the book. Comment that the characters in the photograph are moving. In unison, the students are to open up the book and look at the photograph and report what they see or don’t see. Challenge students to develop a method to test this hypothesis, which appears to be untestable.
Philosophy of Science: Thomas Kuhn
James Burke’s PBS series “Connections” can be helpful to illustrate how paradigm shifts and discoveries in one field “trigger” change in another field.
Wadsworth’s Research Methods Workshop
psychology_d/templates/student_resources/workshops/resch_wrk.html
The Wadsworth’s Research Methods Workshop has a link entitled Experimental Methods that focuses on the types of variables that are present in experiments. First, experimental methods are distinguished from non-experimental approaches. Then, general types of variables are reviewed, including independent, dependent, and subject variables (as well as quantitative and categorical variables). The notion of confounds is introduced, and students are afforded practice with the provided research examples in recognizing and eliminating confounds. Several examples also are provided to give students guidance on how to select levels of an independent variable.
Internet Resources
The Jane Goodall Institute (
Jane Goodall represents an effective and worthwhile illustration of naturalistic observation. The website describes her work and her current activism for chimpanzees and the environment.
Infomercials (
This site describes top selling infomercial products and is good fodder for practicing developing methods to test the product’s claims. Especially intriguing are the exercise products that claim incredible health benefits.
The Karl Popper Web (
Popper’s contributions to science are described on this website. In addition, an email based open forum is offered to those who are interested in discussing Popper’s ideas.
Web Center for Social Research Methods (
Here there are some links to various useful resources pertaining to research methods. The methods tutorials are especially beneficial for this chapter.
National Undergraduate Research Clearinghouse (
Undergraduate students often engage in research and produce scholarly works. This site allows the user to search for research. You may wish to use this site to search for examples of different types of methods.
The Fallacy Files (
Given that the chapter speaks to the role of logic in science, it might be interesting to peruse this site for its collection of logical fallacies (e.g., the masked man fallacy, four-term fallacy, and red herring).
Suggested Readings
Anderson, S.J., & Verplanck, W.S. (1983). When walls speak. What do they say? Psychological Record, 3, 341-359.
Arluke, A., Kutakoff, L., & Levin, J. (1987). Are the times changing? An analysis of gender differences in sexual graffiti. Sex Roles, 16, 1-7.
Interesting research on the content of graffiti in public restrooms.
Cialdini, R. B., & Kenrick, D.T. (1976). Altruism as hedonism: A social development perspective on the relationship of negative mood and helping. Journal of Personality and Social Psychology, 34, 907-914.
Latane, B., & Darley, J.M. (1968). Group inhibition of bystanders intervention in emergencies. Journal of Personality and Social Psychology, 10, 215-221.
Classic research on bystander behavior.
Levine, R. V. (1990, September-October). The pace of life. American Scientist, pp. 451-459.
A summary of Levine's work on the pace of life across cities in the U.S. and six other countries. Explains the Pace of Life Index and how measurements were made by the researchers.
Research Activities for Students
The goals of the research activities are to: (1) relate Chapter 2 on an applied learning dimension, and (2) get students involved in research.
1. Altruism Research: Library Activity. Go to the library and find two articles on altruism. Answer the following questions separately for each: (a) How was altruism operationally defined? (b) Was the study conducted in the field or a laboratory? (c) Was the study correlational or experimental? (d) What were the author's conclusions? Comment on the generalizability of these findings. See the Suggested Readings list for more on the subject of altruism and the generalizability of this issue (Cialdini & Kenrick, 1976).
2.Children and Shyness: Design your own research study. Go to the library and find two research articles on shyness in children. Through examination of the operational definitions and descriptions of shyness within the articles, identify five behaviors that you could observe in a naturalistic study of children on a school playground. Finally, after researching this topic in the library, generate a hypothesis related to shyness. Design a correlational or experimental study that tests this hypothesis.
Hypothesis checklist: Address the following issues.
a.What is the independent variable?
b.Is the independent variable manipulated by the investigator?
c.What is the dependent variable?
d.What outcome are you predicting?
eWhat relationship are you expecting between the variables?
f.What types of conclusions will be appropriate?
3. Pace of Life Research. Naturalistic Observation. Conduct a naturalistic observational study on the pace of life in your city. Go to a shopping mall or the downtown center of business, and measure the following behaviors: (a) percentage of people wearing watches, (b) walking speed. Begin by operationally defining how you will measure these variables. Next, describe your procedure--that is, how you will collect data. Design a coding sheet for your observations that includes: (a) location, (b) date, (c) time of day you begin and end observation, (d) behaviors to be observed. You may also be interested in demographic information like gender and age. Be observant of patterns and trends. Note any limitations. Was it difficult to remain unobtrusive? Include graphs and tables to illustrate your findings. Be prepared to discuss your findings in class. See the Suggested Readings list for more on Levine's (l990) Pace of Life study.
4.Graffiti in Public Restrooms. Design a Coding Sheet and Conduct a Naturalistic Study. Design a coding sheet that will be used to conduct a naturalistic observation of graffiti content found in public restrooms. The coding sheet should consist of simple categories (e.g., sexual versus non-sexual) and more complex categories (e.g., homosexual, heterosexual, and political). Identify the categories as column headings. Observe several public restrooms for graffiti to collect data. Mark the frequency of observations in each category. Specify information about the setting (e.g., women's restroom on a university campus, etc.). Be prepared to discuss your observations in class. Compare the findings of those who observed male versus female restrooms to determine if the graffiti content is similar in both settings. Find two research articles that address this issue (See the suggested reading list).
5. Media and Violence: Cause and Effect. Research Activity. Research online references such as PsycINFO and PubMedto find titles of scientific studies on media and violence. What words other than cause and effect are used to imply a cause and effect? List three examples.
Handout 2-1
The Role of the Scientist
Method / Description / The role of scientistNaturalistic Observation
Correlational Approach
Experimental method
TESTBANK
MULTIPLE CHOICE
1.A formally stated expectation concerning the outcome of an experiment is called:
a. / a theory.b. / induction.
c. / a hypothesis.
d. / empiricism.
ANS:CPTS:1REF:Introduction
2.If you learn about the world through observation and experimentation, you are relying upon:
a. / a hypothesis.b. / inference.
c. / deduction.
d. / empiricism.
ANS:DPTS:1REF:Introduction
3.A scientist will evaluate a hypothesis by using:
a. / empiricism.b. / a theory.
c. / naturalistic observation.
d. / exploratory research.
ANS:APTS:1REF:IntroductionMSC:WWW
4.If little is known about a psychological phenomenon, then ____ is the most appropriate method to use to study it.
a. / the correlational approachb. / the experimental approach
c. / the post hoc approach
d. / naturalistic observation
ANS:DPTS:1REF:Introduction
5.Professor Campbell is studying memory by using mathematical operations. She is using:
a. / a correlational approach.b. / modeling.
c. / a post hoc approach.
d. / a retrospective approach.
ANS:BPTS:1REF:Introduction
6.A scientific approach that attempts to establish an artificial system which can produce behaviors similar to those observed in humans or other animals is called:
a. / exploratory research.b. / the correlational approach.
c. / the experimental method.
d. / modeling.
ANS:DPTS:1REF:Introduction
7.If we were interested in knowing whether early childhood experiences contributed to the later development of personality disorders, we would likely use:
a. / the experimental method.b. / exploratory research.
c. / naturalistic observation.
d. / the retrospective method.
ANS:DPTS:1REF:Introduction
8.Behavior is to experience as ____ is to ____.
a. / correlational; experimentalb. / experimental; qualitative
c. / quantitative; qualitative
d. / naturalistic; experimental
ANS:CPTS:1REF:IntroductionMSC:WWW
9.An approach that emphasizes the subjective aspects of experience uses:
a. / qualitative methods.b. / quantitative methods.
c. / the retrospective method.
d. / modeling.
ANS:APTS:1REF:Introduction
10.To engage in a scientific approach to the study of human behavior, we would use:
a. / the experimental method.b. / the correlational approach.
c. / naturalistic observation.
d. / any of these
ANS:DPTS:1REF:Introduction
11.In the ____ approach, individuals are videotaped discussing a particular topic. They then watch the video separately and comment on how they thought or felt during specific segments.
a. / naturalisticb. / quantitative
c. / action-project
d. / film interview
ANS:CPTS:1REF:Introduction
12.Dr. Nathan wants to study how pythons behave in their native habitat. He sets up hidden cameras in the rain forest to observe the snakes while he remains undetected. Dr. Nathan is using the ____ method of conducting research.
a. / experimentalb. / inferential
c. / correlational
d. / naturalistic observation
ANS:DPTS:1REF:Naturalistic Observation
13.Which of the following best describes naturalistic observation?
a. / You calculate internal and external validity.b. / You look for an association between two variables.
c. / You just watch.
d. / You determine if there is a cause-and-effect relationship.
ANS:CPTS:1REF:Naturalistic Observation
MSC:WWW
14.If you wanted to study play behavior in preschool children, the ideal approach would most likely be:
a. / modeling.b. / naturalistic observation.
c. / the retrospective method.
d. / the experimental method.
ANS:BPTS:1REF:Naturalistic Observation
15.In naturalistic observation, the experimenter ____, whereas in the experimental method, the experimenter ____.
a. / is passive; is activeb. / is active; is passive
c. / observes; does not observe
d. / influences the participant's behavior; does not influence the participant's behavior
ANS:APTS:1REF:Naturalistic Observation
16.Naturalistic observation tends to be:
a. / theoretical rather than empirical.b. / concerned with determining causes of behavior.
c. / descriptive rather than explanatory.
d. / deductive rather than inductive.
ANS:CPTS:1REF:Naturalistic Observation