Question 1

Continuous data use which of the following scales of measurement?
A) Interval and ordinal
B) Ordinal and ratio
C) Ratio and interval
D) a and c

Accepted Answer

Continuous data use interval and ratio scales of measurements. Discrete data can use nominal or ordinal scales of measurement.

Question 2

Which type of sampling prevents the possibility of selection bias by the researcher?
A) Purposive sampling
B) Convenience sampling
C) Systematic sampling
D) Random sampling

Accepted Answer

Random sampling prevents the possibility of selection bias by the researcher.

Question 3

Which term is used when discussing numeric characteristics of samples?
A) Calibrated
B) Statistic
C) Inferential
D) Variable

Accepted Answer

When one is discussing numeric characteristics of samples, the term statistic is used. A sample is a portion or subset of the entire population that can provide meaningful information about the entire population.

Question 4

Which of the following scales of measurement is the most powerful?
A) Nominal
B) Ordinal
C) Interval
D) Ratio

Accepted Answer

As listed, each scale of measurement takes on the characteristics of the previous one, making ratio the most powerful measurement. Nominal scales are named categories only, ordinal scales are the same as nominal plus the categories are in order, interval scales are the same as ordinal plus have equal intervals between categories, and ratio scales are the same as interval scales plus have a meaningful or true zero point.

Question 5

The first step in beginning a research study is which of the following?
A) The formulation of a hypothesis
B) The formulation of an idea
C) Gathering data
D) Testing the null hypothesis

Accepted Answer

The first step is the formulation of an idea. The idea is usually formed from a question that has been raised by a researcher. The question may arise from a simple observation or thought. From simple notions such as these, a research question or problem can be formulated.

Question 6

A normal distribution assumes that approximately what percentage of the population falls within one standard deviation (SD) of the mean?
A) 50%
B) 68%
C) 75%
D) 90%

Accepted Answer

A normal distribution assumes that approximately 68% of the population fall within one SD of the mean, approximately 95% fall within two SDs of the mean, and 99% lie within three SDs of the mean. The plotting of these data on a graph results in a bell-shaped curve.

Question 7

What is the median of the following distribution of scores-3, 4, 4, 6, 8, 10, 14?
A) 4
B) 6
C) 7
D) 14

Accepted Answer

The median represents the exact middle score or value in an ordered distribution of scores; it is the point above and below which 50% of the scores lie. When the total number of scores is even, the sum of the two middle scores, divided by 2, provides the median.

Question 8

A result presented as either a positive or negative relationship is the result of which statistical method?
A) Confidence
B) A normal distribution
C) Correlation
D) Median

Accepted Answer

Correlation is a statistical method for determining whether a variation in one variable may be related to a variation in another variable. When the relationship is positive, it is predicted that as the value of one variable increases, the other also increases. In contrast, a negative correlation shows an inverse relationship among variables.

Question 9

Interrater reliability refers to which of the following?
A) The extent that two or more raters obtain the same result when using the same instrument to measure a concept
B) The same rater making the same assessment on two or more occasions
C) Gathering data that were intended to be collected
D) a and c

Accepted Answer

Interrater reliability refers to the extent that two or more raters obtain the same result when using the same instrument to measure a concept. Intrarater reliability or consistency refers to the same rater making the same assessment on two or more occasions. Validity is concerned with gathering data that were intended to be collected.

Question 10

Which of the following is the most common nonparametric test?
A) T-test
B) Analysis of variance (ANOVA)
C) Chi-square test
D) Standard deviation

Accepted Answer

The most commonly used nonparametric test is the chi-square test. This test may be used to analyze questionnaire data and to determine whether a relationship exists between two variables. The chi-square test is used to examine the differences between observed and expected frequencies.

Question 11

Which of the following is most often used to measure interval and ratio variables?
A) Mean
B) Median
C) Mode
D) Variance

Accepted Answer

Variance is most often used to measure interval and ratio variables. It is a method of ascertaining the way individual variables are located around the mean. Variance is a step in determining the standard deviation (SD) and is equal to the square of the SD.

Question 12

Which of the following is most often used to display data representing interval- or ratio-scaled variables that are continuous in nature?
A) Frequency polygon
B) Histogram
C) Bar graph

Accepted Answer

A frequency polygon is used to represent data that are continuous in nature. A histogram is used most often to represent interval- or ratio-scaled variables that are continuous in nature. A bar graph is most often used to display nominal or ordinal data that are discrete in nature.

Question 13

The term used to describe the average of the group is which of the following?
A) Mean
B) Median
C) Mode
D) Standard deviation

Accepted Answer

The mean is the average of the group. It is a sum of all values divided by the number (n) of items. The median represents the exact middle score or value in an ordered distribution of scores. The mode is the score or value that occurs most frequently in a distribution of scores.

Question 14

When the confidence interval is 95%, what is the statistical probability that the observed results or differences between study and control groups are due purely to chance?
A) 100%
B) 95%
C) 5%
D) 0%

Accepted Answer

There is a 5% chance when the CI is 95% that the observed results or differences between study and control groups are due purely to chance and do not represent a true difference caused by the independent variable.

Question 15

Of the following, which term is used in regard to numeric characteristics of the population?
A) Parameter
B) Control
C) Correlation
D) Independent variable

Accepted Answer

Parameter is used in regard to numeric characteristics of the population. Population can be defined as the entire group or whole unit of individuals having similar characteristics from which the results of an investigation can be inferred. Target population is the population from whom the information is collected.

Question 16

Systematic sampling is best described by which of the following?
A) The random selection of subjects from two or more strata of the population
B) Involves the selection of subjects by including every nth person in a list
C) Provides a sample, through personal judgment, of subjects who would be most representative of the population
D) Provides a group of individuals who are most readily available to be subjects in the study

Accepted Answer

Systematic sampling involves the selection of subjects by including every nth person in a list.

Question 17

Which of the following is true concerning independent and dependent variables?
A) The dependent variable is controlled or manipulated by the researcher.
B) The independent variable is thought to depend on or to be caused by the dependent variable.
C) The independent variable is controlled or manipulated by the researcher and is believed to cause or influence the dependent variable.
D) a and c

Accepted Answer

The independent variable is controlled or manipulated by the researcher and is believed to cause or influence the dependent variable. The dependent variable is thought to depend on or to be caused by the independent variable. It is the outcome variable of interest.

Question 18

Which of the following types of sampling provides the most external validity, or the degree to which the results of the study can be generalized to settings other than the one included?
A) Stratified sampling
B) Systematic sampling
C) Random sampling
D) Convenience sampling

Accepted Answer

Random sampling provides a method in which each member of a population has an equal chance of being included.

Question 19

Cancer staging for tumors is an example of which scale of measurement?
A) Nominal
B) Ordinal
C) Interval
D) Ratio

Accepted Answer

Ordinal scales of measurement consist of categories of variables in which the categories are in order but there is no equal or defined distance between them. Cancer staging for tumors is grouped into four stages designated by Roman numerals I-IV. It is known that type II is worse than type I and that type III is worse than type II, but each type of cancer is slightly different, making it difficult to define precisely for all cancers.

Question 20

Which of the following is true of the t-test?
A) The t-test is used to analyze the difference between two means.
B) The dependent t-test determines differences in the mean between two independent groups.
C) When the test is used on a single group that yields pretreatment and posttreatment scores, it is known as a t-test for independent samples.
D) a and c

Accepted Answer

The t-test is used to analyze the difference between two means. When the test is used on a single group that yields pretreatment and posttreatment scores, it is known as a t-test for dependent samples. The independent t-test determines differences in the mean between two independent groups.

Quiz 7: Applied Research

Continuous data use which of the following scales of measurement?

Which type of sampling prevents the possibility of selection bias by the researcher?

Which term is used when discussing numeric characteristics of samples?

Which of the following scales of measurement is the most powerful?

The first step in beginning a research study is which of the following?

A normal distribution assumes that approximately what percentage of the population falls within one standard deviation (SD) of the mean?

What is the median of the following distribution of scores-3, 4, 4, 6, 8, 10, 14?

A result presented as either a positive or negative relationship is the result of which statistical method?

Interrater reliability refers to which of the following?

Which of the following is the most common nonparametric test?

Which of the following is most often used to measure interval and ratio variables?

Which of the following is most often used to display data representing interval- or ratio-scaled variables that are continuous in nature?

The term used to describe the average of the group is which of the following?

When the confidence interval is 95%, what is the statistical probability that the observed results or differences between study and control groups are due purely to chance?

Of the following, which term is used in regard to numeric characteristics of the population?

Systematic sampling is best described by which of the following?

Which of the following is true concerning independent and dependent variables?

Which of the following types of sampling provides the most external validity, or the degree to which the results of the study can be generalized to settings other than the one included?

Cancer staging for tumors is an example of which scale of measurement?

Which of the following is true of the t-test?