Question 1

To which scale of measurement can numbers be arbitrarily assigned but which don't have any numerical value?

Accepted Answer

Nominal scales of measurement allow numbers or labels to be arbitrarily assigned to different categories, without any inherent numerical value. For example, assigning numbers to different colors or categories of sports would be considered nominal measurement.

Question 2

The numbers on pool balls are examples of which scale of measurement?

Accepted Answer

The numbers on pool balls are examples of nominal scale measurement because they are used to identify or categorize the balls without implying any sort of ranking or specific order.

Question 3

Which is the only scale of measurement which allows such statements as "Maria is twice as fast at Jose?

Accepted Answer

Ratio scale allows for comparisons of quantitative values with a true meaningful zero point. This means that ratios between values are meaningful, as in the example statement "Maria is twice as fast as Jose". Nominal, interval, and ordinal scales do not allow for ratio comparisons in this way.

Question 4

I like ice cream. My favorite is chocolate. If I can't have chocolate, I'll eat vanilla, If there's no vanilla, I'll take strawberry. My preference for ice cream flavors is an example of the ________________ scale of measurement.

Accepted Answer

The preference for ice cream flavors is based on a ranking order, from most favorite to least favorite. This represents the ordinal scale of measurement.

Question 5

Scales of measurement

Accepted Answer

Scales of measurement are important in determining which statistical procedures are appropriate to be used in analyzing the data obtained from research. Different types of data require different statistical tests, and knowing the scale of measurement helps determine the appropriate analysis method.

Question 6

In an experiment, the _____________ variable is manipulated by the researcher.

Accepted Answer

The independent variable is the variable that is manipulated or changed by the researcher in an experiment. The dependent variable is the variable that is being measured or observed for changes based on the manipulation of the independent variable. Discrete variables refer to variables with finite or distinct values, and extraneous variables are variables that can affect the outcome of the experiment but are not of interest to the researcher.

Question 7

The _____________ variable is what is measured in an experiment to see if it was affected by the ______________ variable.

Accepted Answer

The variable that is being measured or observed is the dependent variable, which is affected by the independent variable (the variable that is being manipulated or changed). Therefore, choice D, dependent and independent variables, is the correct answer.

Question 8

____________ variables can have an unintended effect on the _____________ variable if not controlled.

Accepted Answer

Extraneous variables refer to any variable other than the independent variable that can affect the dependent variable. If not controlled, they can create a false relationship between the independent and dependent variables, leading to inaccurate conclusions. Therefore, B is the best choice because extraneous variables can have unintended effects on the dependent variable if not controlled.

Question 9

In an experiment, the group that is used as a baseline for comparison is called the ______________ group.

Accepted Answer

The control group is used as a baseline for comparison in an experiment. It is not exposed to the independent variable and is used to compare the effects of the independent variable on the experimental group.

Question 10

Extraneous variables should be

Accepted Answer

Extraneous variables are variables that can affect the outcome of an experiment but are not the variables of interest. To ensure the validity of an experiment, extraneous variables should be controlled or kept constant across all groups to avoid their confounding effects. Therefore, the best choice is to maintain them at the same level across all groups.

Question 11

What procedure is used in an experiment that involves all participants having an equal chance of being assigned to any one of the groups?

Accepted Answer

Random assignment ensures that there is an equal chance of participants being assigned to any group, which is important for reducing bias and increasing the validity of the study. Controlled or experimental assignment imply that the researcher has control over the assignment process, which may introduce bias. Equal assignment is not a commonly used term in experimental design.

Question 12

Random assignment ____________________.

Accepted Answer

Random assignment helps eliminate bias by ensuring that each participant has an equal chance of being assigned to any of the groups being studied. It also spreads out preexisting differences between participants among the groups, helping to control for potential confounding variables. By doing so, it helps maintain the integrity of the research by ensuring that any differences observed between the groups can be attributed to the treatment or intervention being studied, rather than to preexisting differences between the participants.

Question 13

In a study to determine the effect of room temperature on concentration, room temperature would be the

Accepted Answer

The independent variable is the variable that is manipulated by the researcher in order to determine its effect on the dependent variable, which is the variable that is being measured. In this case, the researcher is manipulating the room temperature in order to see how it affects concentration, so the room temperature is the independent variable.

Question 14

In a study to determine the effect of caffeine on memory, memory would be the

Accepted Answer

Memory is the variable which is being measured as a result of the manipulation of the independent variable, caffeine. Therefore, memory is the dependent variable.

Question 15

Which type of research can demonstrate cause-and-effect relationship?

Accepted Answer

Only experimentation involves manipulating variables to establish a cause-and-effect relationship. Correlation, surveys, and case studies can suggest correlations but cannot establish causality.

Question 16

In nonexperimental research,

Accepted Answer

In nonexperimental research, the researcher only observes scores without actively manipulating any variables. This means that conclusions cannot be drawn about cause-and-effect relationships, and correlational studies can be used.

Question 17

A study reports that income for males increases by 2% for every 4-inch increase in height. What type of research is involved in this study?

Accepted Answer

The study identifies a relationship between two variables, height and income, without manipulating either variable. This is an example of a correlation study.

Question 18

A study reports that a newly developed non-opioid analgesic medication decreased the amount of pain experienced by people who suffer from migraine headaches. What type of research is involved in this study?

Accepted Answer

The study involved testing a newly developed medication to see if it decreased pain in people with migraine headaches, which is an experiment.

Question 19

The number 47.8367 rounded to the nearest hundredth would be

Accepted Answer

To round to the nearest hundredth, we look at the digit in the thousandths place, which is 6. Since 6 is greater than or equal to 5, we round up the hundredth place, which gives us 47.84. Therefore, the best choice is B.

Question 20

Changing a decimal to a percentage would be accomplished by ________________.

Accepted Answer

To convert a decimal to a percentage, you need to multiply it by 100. For example, to convert 0.75 to a percentage, you multiply 0.75 by 100 to get 75%.

Quiz 1: Introduction to Statistics