Unit 2: Study Questions

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Briefly identify and describe the three goals of the scientific enterprise. (pp. 44-45)

Define hypothesis, variables, and theory. What is required of a scientific theory? How are scientific theories constructed? (pp. 44-45)

Identify and describe the five steps in scientific investigations, as outlined by Weiten and McCann. (pp. 46-48)

Define operational definition, participants (or subjects), and data collection techniques. (p. 46)

Comment: In everyday life, people often use words casually. For example, if we describe ourselves as feeling “full of anxiety,” our listeners will usually get the general idea of what we mean. This practice is unsufficiently precise for psychological research, however. If we use the word “anxiety” in psychological research, we must define it operationally, in terms of the actions or operations used to measure anxiety. For example, anxiety might be measured using physiological measures, such as heart rate and perspiration, or it might be measured using a test in which people rate the extent of their anxiety. The same generally goes for other variables in a psychology experiment: they must be defined precisely through the operations that are used to measure them.

Describe the procedure and results of Dutton and Aron’s (1974) experiment concerning anxiety and sexual attraction. (pp. 47-48)

Describe two advantages of the scientific approach as it relates to the study of behaviour. (pp. 48-49)

Comment: The two features of a scientific approach with respect to behaviour are 1) an insistence on clarity and precision, and 2) avoidance of errors. To avoid errors, scientists take a skeptical attitude, which entails believing things only after they have been proven through experiments or other means of generating data. Scientific skepticism is a way to guard against accepting false data, incorrect facts, and bogus causal relationships. However, once data, facts, and causal relationships have passed the test of skepticism, scientists can then accept these findings as fully and passionately as they formerly applied skepticism. Be careful not to think of scientists as being skeptical about everything, however. Scientists restrict their skepticism to that which has not been proven, and they accept what has been proven. This restrictive skepticism enables scientists to assemble proven facts in understanding the world.

Define experiment. Define and give examples of the independent and dependent variablesthat are encountered in an experiment. Be able to identify examples of these variables in experiments. (pp. 49-50)

Distinguish between experimental and control groups, and explain their relationship in an experiment. Explain why changes in the dependent variable can be attributed to the independent variable in an experiment. (p. 51)

Define extraneous variables and confounding of variables. (p. 51)

Define random assignment of subjects. (p. 51)

Comment: Random sampling is similar to yet different from random assignment. Random sampling refers to drawing a sample from a population in such a way that each member of the population has an equal chance of being part of the selected sample.

Why is it sometimes advantageous to use only one group of subjects who serve as their own control? Define the two broad types of experimental design used in psychology: between-subjects design and a within-subjects design. Be able to cite and recognize original examples of these designs (p. 52)

Comment: The between-subjects design typically involves an experimental group of subjects and at least one control group of subjects. For example, the subjects in an experimental group might be given the drug the researcher is interested in testing, while the subjects in the control group are given a placebo. The researcher will then check to determine whether any significant differences exist between the two groups of subjects.

The within-subjects design does not require a separate control group. In this design, one group of subjects (or even a single subject) acts as their own control. Thus, the researcher might take repeated measures of each subject’s response to different experimental conditions. For example, each subject might be given the placebo first, then the drug the researcher is interested in testing, then the placebo again. This approach is known as an A-B-A design. These designs are useful because they show the effects of a variable on an individual subject rather than on a hypothetical “average subject.”

Is it possible to use more than one independent variable in a single experiment? Explain. Provide and recognize original examples of experiments of this type. (p. 52)

What is an interaction? Be able to cite and recognize novel examples of interactions and to explain the nature of the interaction. (p. 52)

Is it possible to use more than one dependent variable in a single experiment? Explain. Provide and recognize original examples of the use of multiple dependent variables. (p. 52)

Discuss the major advantages and disadvantages of the experimental method. What are field experiments? Be able to cite and recognize novel examples of field experiments (p. 53)

Distinguish between the experimental and the descriptive/correlational research methods. Cite and describe three descriptive research methods: naturalistic observation, case studies, and surveys. (pp. 54-57)

Discuss the major advantages and disadvantages of descriptive/correlational research. What is the strongest disadvantage of descriptive/correlational research? (pp. 56-58)

What are statistics? What are descriptive statistics? (pp. 58-59)

What is central tendency? Define and describe the three measures of central tendency: the median, the mean, and the mode. Which of these measures is most useful? Which measure is unduly influenced by extreme scores? (pp. 59-60)

What is a frequency distribution? What is a symmetrical frequency distribution, a negatively skewed distribution, and a positively skewed distribution. (pp. 59-60)

Comment: You can see three examples of frequency distributions in Figure 2.6.

Define variability. What, in general terms, is a standard deviation? What does a large standard deviation indicate about variability? What does a small standard deviation indicate about variability? (pp. 60-62)

Comment: The measures of central tendency tell us where the centre of a frequency distribution lies. But those measures tell us nothing about how much variability there is in the distribution. The standard deviation provides information about variability. The mean tells us little without the standard deviation.

What are relative measures? What is a percentile score? If your percentile score on the final exam in this course is 10%, have you done relatively well or poorly on the exam? Explain. (p. 61)

When is a correlation said to exist? What is a correlation coefficient? What is a positive correlation? What is a negative correlation? What is the strength of the correlation, and how is this indicated in the correlation coefficient? Provide and recognize original examples of variables that are positively and negatively correlated. (pp. 62-63)

Explain how a correlation relates to prediction and causation. Provide and recognize original examples of two variables that are positively or negatively correlated, but that are not causally related. (pp. 63-64)

What are inferential statistics? What is statistical significance? Explain the distinction between the statistical and the practical significance of research findings. (pp. 64-65)

Comment: Most psychological experiments make use of inferential statistical tests to determine whether there was a cause-effect relationship between the independent variable and the dependent variable. So if you go on in psychology, it is important to thoroughly understand descriptive and inferential statistics. However, some behavioural scientists avoid the use of inferential statistics in favour of the more simple use of graphs that display the influence of the independent variable on the dependent variable. The use of graphing for this purpose is characteristic of the field of applied behaviour analysis, which tends to use within-subjects experimental designs. Athabasca University’s Psychology 365: Behaviour Modification Principles covers these approaches to research.

Comment: Although Weiten and McCann do not explicitly discuss statistical methods, it is important that you understand the basic concepts so that you can more fully understand the empirical method. Appendix B of the text (pp. A-7-14) provides a brief introduction to this topic. To help you understand terms you might be exposed to in scientific papers, a brief explanation of the null hypothesis and statistical significance is provided as follows.

The null hypothesis is the assumption in an experiment that any difference between groups is due merely to chance.

When we reject the null hypothesis, we conclude that we have found statistically significant results. In other words, we can assume that any difference in results is unlikely to be due to chance.

Statistical significance is said to exist when the probability that the observed findings are due to chance is very low, usually less than five chances in 100. This means that if the null hypothesis is correct and we conduct our study 100 times, we will get results such as those observed only five times out of 100. The requirement that there be fewer than five chances in 100 that research results are due to chance is the minimum requirement for statistical significance. When this requirement is met, we say the results are significant at the 0.05 level. If researchers calculate that there is less than a 1 in 100 chance that their results are due to chance, the results are significant at the 0.01 level. Thus, there are several levels of significance that you may see cited in scientific articles. Of course, if the results were significant at a 0.1 level of significance (or a 1 in 10 chance) we could not reject the null hypothesis.

What is replication? Why is it useful in scientific progress? (p. 62)

Comment: Replications are simply reruns of experiments, but often a rerun takes place under different conditions than the original experiment. In a replication, the same basic experiment is conducted again to determine whether it will produce the same findings as the original experiment. Within psychology and the other sciences, it is often difficult to publish research that fails to replicate the original work. The data from such failed replications are sometimes called “negative results.”

What is a meta-analysis? What information can a meta-analysis provide that cannot be provided by a single experiment? (p. 66)

Name and describe the following flaws that can be present in psychological research: sampling bias, placebo effects, distortions in self-report data, and experimenter bias. Be able to cite and recognize original example of these flaws. (pp. 66-69)

Define sample and population. Provide and recognize original examples of each. Be sure you are able to distinguish between representative, and biased or non-representative samples. (pp. 66-67)

Be able to cite and provide original examples of research in which an apparent experimental effect could be due to a placebo effect. (pp. 67-68)

Define social desirability bias. Provide and recognize original examples of this source of bias. What is a response set? What are halo effects? Explain why response sets and halo effects can pose problems for researchers. (pp. 68-69)

Define double-blind procedure. Explain why this procedure is useful. (p. 69)

What is Internet-mediated research? Describe the advantages and disadvantages of this type of research. (pp. 72-73)

Discuss the controversy over the use of deception in psychological research. (pp. 73-74)

Comment: A key element in this chapter is Weiten and McCann’s focus on ethical considerations. While they focus on experimental research and most obviously on the use of deception, other clear examples of abuse in clinical domains have occurred in recent history. Consider that in the United Kingdom in the mid-1970s homosexuality was a criminal offence punishable by a prison term or by treatment using electrical shock therapy to decondition the homosexual individual to homosexual urges. Although perceptions about homosexuality have changed radically since then, most psychologists at that time did not recognize these treatments as abusive. A consciousness of ethical and human rights considerations benefits everyone.

Correction: Note that on page 83, Practice Question 14 asks about evidence relating to the effects of deception on participants. Actually, the text does not provide research findings about this although answer B - that deception is probably not that harmful - is generally thought to be true for most current uses of deception.

What is a journal? What is a journal article? What is an abstract? Where can you find abstracts of psychological research? (pp. 77-78)

Describe the standard organization of a published journal article, including the order and main content of each part. (pp. 78-79)

Discuss the limitations of anecdotal evidence. Be able to provide and recognize original examples of anecdotal evidence. (pp. 80-81)