Question 1

A researcher investigates the relationship between age (10 years, 12 years, and 14 years) and gender on percent body fat. What is (are) the dependent variable(s)?

Accepted Answer

The dependent variable in this study is percent body fat, as this is the variable that is being measured and examined in relation to age and gender. Age and gender are independent variables that are being manipulated or observed to determine their effect on percent body fat.

Question 2

A researcher examines the effects of mental imagery (none, 5 minutes, 25 minutes) on shooting accuracy in novice, intermediate, and expert archers. What is (are) the confounding variable(s)?

Accepted Answer

The answer of A researcher examines the effects of mental...

Question 3

Which threat to internal validity is related to an uneven loss of subjects from an investigation?

Accepted Answer

Experimental mortality, also known as attrition, occurs when participants drop out of a study before it is complete. If there is an uneven loss between the experimental and control groups, it can threaten the internal validity of the study as the groups may no longer be equivalent.

Question 4

Which threat to internal validity is associated with extreme scores in repeated measurements?

Accepted Answer

Extreme scores in repeated measurements are associated with statistical regression, which refers to the tendency of extreme scores to move closer to the mean with repeated measures.

Question 5

Which threat to internal validity is related to unexpected events?

Accepted Answer

Local history refers to unexpected events that occur during the study that may affect the outcomes, such as a natural disaster or a political event. These events can threaten the internal validity of the study as they may impact the outcomes and make it difficult to determine if the intervention was truly effective or if the results were due to the unexpected event.

Question 6

Which of the following is a threat to external validity?

Accepted Answer

Pretest sensitization is a threat to external validity because it can affect how participants respond to the treatment, making it difficult to generalize the results to a broader population that did not receive the pretest.

Question 7

What does regression to the mean predict if a subject obtains an extreme score on a measurement and then is remeasured?

Accepted Answer

Regression to the mean predicts that extreme scores will tend to be followed by less extreme scores when the measurement is remade. Therefore, the second score will be less extreme than the first.

Question 8

What is true about the null hypothesis?

Accepted Answer

The null hypothesis is the statistical hypothesis that predicts no relationship exists between variables or that there is no significant difference between groups. It is not always false, as it is important to consider and test both the null and alternative hypotheses. It is also not usually the same as the research hypothesis, as the research hypothesis is the hypothesis being investigated by the researcher. The null hypothesis is not predicting a treatment effect, but rather predicting no effect.

Question 9

Suppose you conduct an experiment to examine the effects of strength training on three factors: muscular endurance, muscular strength, and muscular power. Which of the following is true?

Accepted Answer

The question does not provide enough information to determine the dependent, independent, or control variables. The experiment is examining the effects of strength training on three factors, but it is not specified which variable is being manipulated (independent variable) and which variables are being measured (dependent variables) or kept constant (control variables).

Question 10

Toby thinks that physical ability is affected by age, gender, weight, and physical activity. What is (are)Toby's dependent variable(s)?

Accepted Answer

The dependent variable is the variable being measured or tested, and in this case, it is physical ability. Age, gender, weight, and physical activity are potential independent variables that may affect physical ability.

Question 11

The statements, "Men have a greater aerobic capacity than women" and "Men have a greater aerobic capacity than women because of a larger cardiorespiratory system" are examples of what levels of knowledge, respectively?

Accepted Answer

The first statement simply describes a difference in aerobic capacity between men and women, while the second statement goes on to provide an explanation for why this difference exists. Therefore, the statements are examples of the levels of knowledge of description and explanation, respectively.

Question 12

What name is given to the phenomenon in which subjects' performances change because they recognize they are in an experimental treatment?

Accepted Answer

The Hawthorne effect refers to the phenomenon in which subjects' performances change because they recognize they are in an experimental treatment. This effect occurs when individuals modify their behavior as a result of being observed or because they are aware they are a participant in a study.

Question 13

Choose the TRUE statement about dependent variables.

Accepted Answer

Dependent variables are measured, not set or manipulated. They are the outcome variable that is being studied and is dependent on the independent variable.

Question 14

In a study to determine whether giving different doses of a drug affects the hematocrit of old and young males and females, what is the dependent variable?

Accepted Answer

The dependent variable is the variable that is being measured and affected by the independent variable, which is the drug dose in this case. In this study, the hematocrit level is the dependent variable as it is being measured to determine the effect of different drug doses. The other options (males and females) are not the dependent variables as they are the groups being studied and not the variable being measured.

Question 15

What is the lowest level of measurement required for parametric statistics?

Accepted Answer

Parametric statistics require at least interval level of measurement. It involves the use of techniques such as t-tests, ANOVA, and linear regression, which assume that the data follows a normal distribution and that the variances of the groups being compared are homogeneous. Interval level data allows for accurate mathematical operations such as addition and subtraction, which are necessary for these techniques.

Question 16

The following statement describe the basic purpose, technique, or result of some research projects.
-In this study, a small sample of subjects was selected for study, and the research hypothesis was modified as the study progressed.

Accepted Answer

The statement indicates that the study involved manipulating an independent variable to observe its effects on a dependent variable. The fact that the hypothesis was modified suggests that the researchers were attempting to test a specific causal relationship between variables, which is a characteristic of experimental research. The use of a small sample is also more common in experimental research, as it allows for more precise control and measurement of variables.

Question 17

The following statement describe the basic purpose, technique, or result of some research projects.
-Several groups were exposed to different methods of learning the forward roll to determine which method resulted in the most efficient learning.

Accepted Answer

The statement describes an experimental study where different methods of learning the forward roll were tested to determine the most efficient way of learning.

Question 18

The following statement describe the basic purpose, technique, or result of some research projects.
-The U.S. Centers for Disease Control and Prevention report on the percentage of American adults who meet the U.S. Physical Activity Guidelines.

Accepted Answer

The statement describes a descriptive study, as it reports on the percentage of American adults who meet the U.S. Physical Activity Guidelines without manipulating any variables or conducting experiments.

Question 19

The following statement describe the basic purpose, technique, or result of some research projects.
-To reduce the Hawthorne effect, the researcher met with the control group the same number of times and for the same amount of time as she did with the treatment groups.

Accepted Answer

The mention of a control group and treatment groups indicates that this statement describes an experimental study. The purpose of the technique was to reduce the Hawthorne effect, which is a common issue in experimental studies where participants may alter their behavior due to being observed or studied. By treating the control group and treatment groups equally, the researcher can better isolate the effects of the independent variable on the dependent variable.

Quiz 1: Research Methods

A researcher investigates the relationship between age (10 years, 12 years, and 14 years) and gender on percent body fat. What is (are) the dependent variable(s) ?

A researcher examines the effects of mental imagery (none, 5 minutes, 25 minutes) on shooting accuracy in novice, intermediate, and expert archers. What is (are) the confounding variable(s) ?