(A) studying improves exam grades.

(B) a relationship exists between studying and exam grades.

(C) a significant correlation exists between studying and exam grades.

(D) anyone who does not study will do poorly on the exam.

(E) better students tend to study more.

(B) a relationship exists between studying and exam grades.

Jen has established a relationship, or correlation, between the two variables she is studying. However, since she has not conducted an experiment, Jen does not know whether a cause-andeffect relationship occurs between studying and earning high grades on the exam. Therefore, Jen does not know if studying improves exam grades. Although Jen has found a correlation between studying and exam grades, whether or not that correlation is significant can be determined only through the use of inferential statistics. Even if the correlation were significant, it would not guarantee that if someone did not study, he or she would do poorly on the test. Finally, Jen’s correlation does not tell us that better students study more. In fact, it tells us nothing about better students, not even what is meant by that term.

]]>(A) field experiment

(B) informal survey

(C) case study

(D) naturalistic observation

(E) ethnography

(D) naturalistic observation

Charlotte is using naturalistic observation. As a student herself, she can observe the fingerpainting table unobtrusively. She does not interact with the finger painters; she merely observes. Since Charlotte does not manipulate an independent variable nor attempt to control any aspect of her study, she is not using any kind of experiment. She did not ask the participants questions as she would have if she were conducting a survey. She did not focus on a single participant or a small group of participants as she would have if she had been interested in putting together a case study. Finally, Charlotte has not conducted ethnographic research. Ethnography is a type of research in which the researcher immerses himself or herself in another culture and then describes it. Ethnography is a method most commonly employed by anthropologists.

]]>(A) How fast the mice are at the start.

(B) When the mice run the maze.

(C) The population from which he selected his subjects.

(D) How frightened the mice are before the experiment.

(E) Where the mice run the maze.

(C) The population from which he selected his subjects.

A confounding variable is anything that differs between the control and experimental group besides the independent variable. How fast and frightened the mice are at the onset of the experiment are potential participant-relevant confounding variables. When and where the experiment takes place are possible situation-relevant confounding variables. However, the population from which Vincenzo selected his mice is not a confounding variable; they all came from the same population. True, the population can be flawed. For instance, it can be very homogeneous and thus fail to reflect how other mice would perform under similar conditions. However, such a flaw is not a confounding variable.

]]>I. Picking out of a hat to assign each of three classes to an experimental condition.

II. Having a computer generate a random list of 100 high school students.

III. Approaching any 50 students during sixth-period lunch.

(A) I only

(B) II only

(C) III only

(D) I and II

(E) I, II, and III

(B) II only

Of the three methods presented, only having a computer generate a random list of names is an example of random sampling. The first example illustrates random assignment and not random sampling. Sampling is the process of choosing a group of participants from a population. Once sampling has been completed, one might assign the participants to conditions as described in I. Finally, approaching 50 students during a lunch period does not constitute random sampling even if the person who picks the people tries to do so randomly. Remember that the word random has a very specific meaning in the context of research. Random sampling means that all members of the population had an equal chance of being selected, and people are unable to be so scrupulously unbiased.

]]>(A) scatter plots.

(B) descriptive statistics.

(C) histograms.

(D) inferential statistics.

(E) means-end analysis.

(D) inferential statistics.

Jose needs to compare the performances of the two groups using inferential statistics to determine whether or not the experimental group’s performance was significantly better. Scatter plots are used to graph correlations. Jose would certainly be interested in descriptive statistics as well, but he would not know whether or not his hypothesis had been supported until he used inferential statistics. Histograms are bar graphs, and means-end analysis is a problemsolving technique.

]]>(A) symmetrical.

(B) normal.

(C) positively skewed.

(D) negatively skewed.

(E) a straight line.

(C) positively skewed.

Sandy’s perfect score is an outlier and will therefore skew the distribution. Since it is a high score in a distribution of low scores, the distribution will be positively skewed.

]]>(A) 4

(B) 5

(C) 5.5

(D) 6

(E) 6.5

(B) 5

The median of the distribution is 5. The problem is easier if you put the scores in order: 2, 3, 4, 6, 7, 9. Since the distribution has an even number of scores, there is no middle score and you must average the two middle scores, 4 and 6.

]]>(A) −3

(B) −1.5

(C) +0.67

(D) 1.5

(E) +3

(E) +3

Tamar’s z score is +3. Z scores measure the distance of a score from the mean in units of standard deviation. Since the mean is 100 and the standard deviation is 15, Tamar’s score is 3 standard deviations above the mean.

]]>(A) Human subjects can be deceived for experimental purposes and animals cannot.

(B) Animal subjects can be placed at much greater physical risk than human subjects can.

(C) Human subjects must be chosen much more carefully than animal subjects.

(D) If humans might physically suffer because of the study, the suffering must be minimal, in contrast to animal studies where any amount of suffering is ethical if it helps to further a clear scientific purpose.

(E) Environmental conditions for human studies must be monitored much more closely than they are in an animal study.

(B) Animal subjects can be placed at much greater physical risk than human subjects can.

Within the limits imposed by the guidelines, researchers can physically harm animals if the harm is justified by the nature of the experiments. Deception is obviously not an issue applicable to animal research. Researchers must keep suffering to a minimum, so “any amount” is not an appropriate response (choice D). Animal subjects must be chosen carefully (from accredited commercial sources) and their environment must follow strict guidelines, so choices C and E are also incorrect.

]]>(A) improper sampling procedure

(B) risk of long-term harm

(C) clear scientific purpose

(D) debriefing

(E) anonymity

(B) risk of long-term harm

Milgram’s experiments involved considerable risk of long-lasting stress and anxiety for his subjects. The scientific purpose of Milgram’s study is not disputed, and he debriefed participants and provided for anonymity of individual results.

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