Question 1

Inferential statistics are used to assess the importance of experimental results.

Accepted Answer

The answer of Inferential statistics are used to assess the...

Question 2

The Pearson product?moment correlation coefficient is referred to as
A) z-score.
B) s.d.
C) r.
D) p.c.c.

Accepted Answer

The Pearson product-moment correlation coefficient is commonly denoted by "r", which measures the strength and direction of a linear relationship between two variables.

Question 3

In comparison with one-tailed tests, two-tailed tests are
A) less conservative.
B) more conservative.
C) less likely to lead to a Type II error.
D) more likely to lead to a Type I error.

Accepted Answer

Two-tailed tests are more conservative because they split the alpha level between two tails of the distribution, requiring more extreme test statistics to reject the null hypothesis.

Question 4

Simple analysis of variance is used in designs having
A) one independent variable.
B) more than one independent variable.
C) more than one independent variable (IV) but less than four IVs.
D) more than one dependent variable.

Accepted Answer

Simple analysis of variance (ANOVA) is used when there is only one independent variable to assess the statistical significance of the mean differences among the levels of the independent variable.

Question 5

The Mann-Whitney U test is
A) nonparametric.
B) distribution free.
C) designed for two groups of scores.
D) all of these

Accepted Answer

The Mann-Whitney U test is nonparametric, distribution free, and designed for comparing two groups of scores, making all of these statements correct.

Question 6

In describing an array of data, psychologists typically present two descriptive statistics, the mean and the variance.

Accepted Answer

The answer of In describing an array of data, psychologists...

Question 7

If a person's score is part of a normal distribution of scores, we can determine the relative rank of that score if we know
A) the person's score.
B) the mean of the distribution.
C) the standard deviation of the distribution.
D) we must know all of these

Accepted Answer

To determine the relative rank of a person's score within a normal distribution, it is necessary to know the person's score, the mean of the distribution, and the standard deviation of the distribution. These pieces of information allow for the calculation of a z-score, which can then be used to determine the score's percentile rank within the distribution.

Question 8

The larger the sample, the more we can trust the sample ___________ to be an estimate of the population ___________.
A) mean; mean
B) standard error of the mean; standard deviation
C) standard error of the mean; variance
D) difference; mean

Accepted Answer

The larger the sample size, the more reliable the sample mean becomes as an estimate of the population mean, due to the law of large numbers which states that as a sample size grows, its mean gets closer to the average of the whole population.

Question 9

The Wilcoxon signed-ranks test
A) is used for between-subjects designs.
B) takes into account both the magnitude and the direction of the difference between paired scores.
C) cannot be used for within-subjects designs.
D) is a parametric test.

Accepted Answer

The Wilcoxon signed-ranks test is a non-parametric statistical test that compares two related samples, matched samples, or repeated measurements on a single sample to assess whether their population mean ranks differ. It is used for within-subjects designs (not between-subjects) and considers both the magnitude and direction of differences between paired scores, unlike parametric tests which assume a specific distribution in the data.

Question 10

Which of the following is a parametric test?
A) Mann-Whitney U Test
B) sign test
C) t test
D) Test of Independence

Accepted Answer

The answer of Which of the following is a parametric...

Question 11

The power of a statistical test refers to its ability to
A) reject false null hypotheses.
B) reject false experimental hypotheses.
C) reject true null hypotheses.
D) reject true experimental hypotheses.

Accepted Answer

The power of a statistical test is its ability to correctly reject false null hypotheses, meaning it can detect an effect or difference when one truly exists.

Question 12

The median is often used because it is insensitive to extreme scores.

Accepted Answer

The median is less affected by outliers and extreme scores than the mean, making it a preferred measure of central tendency when dealing with skewed distributions.

Question 13

Which of the following is NOT a measure of dispersion?
A) range
B) standard deviation
C) variance
D) median

Accepted Answer

Median is a measure of central tendency, not dispersion. Measures of dispersion include range, standard deviation, and variance, which describe the spread of data points.

Question 14

In a multifactor analysis of variance, how the variables affect one another is called
A) a main effect.
B) an interaction effect.
C) an experimental effect.
D) a variance effect.

Accepted Answer

An interaction effect in a multifactor analysis of variance refers to how the levels of one factor affect the outcome variable differently at different levels of another factor, indicating that the effect of one variable depends on the level of another variable.

Question 15

The inflection point in the normal curve is _____________ from the mean.
A) less one standard deviation
B) two standard deviations
C) three standard deviations
D) one standard deviation

Accepted Answer

The inflection points on a normal curve, where the curve changes from concave to convex or vice versa, are located exactly one standard deviation away from the mean on either side.

Question 16

In a histogram, the values for the dependent variable are displayed on the ordinate (Y-axis) and the frequency with which each value of the dependent value occurred is displayed on the abscissa (X-axis).

Accepted Answer

The answer of In a histogram, the values for the...

Question 17

In hypothesis testing, both the magnitude of the difference and the direction of the difference between two groups are considered in
A) two-tailed tests.
B) one-tailed tests.
C) parametric tests.
D) nonparametric tests.

Accepted Answer

In one-tailed tests, both the magnitude and the direction of the difference are considered because the test is designed to detect an effect in one specific direction.

Question 18

The F statistic is
A) the ratio of between-group variance to within-group variance.
B) between-groups variance minus within-groups variance.
C) within-groups variance minus between-groups variance.
D) a measure of error variance.

Accepted Answer

The F statistic is used in analysis of variance (ANOVA) and is calculated as the ratio of between-group variance to within-group variance. This helps in determining whether the means of several groups are equal.

Question 19

The number of participants in a study is denoted by
A) s.
B) n.
C) z.
D) r.

Accepted Answer

In statistical studies, "n" is commonly used to represent the number of participants or observations.

Question 20

If experimental treatments produce an effect,
A) between-groups variance will increase.
B) between-groups variance will decrease.
C) within-groups variance will increase.
D) within-groups variance will decrease.

Accepted Answer

When experimental treatments produce an effect, it means that the groups being compared are becoming more different from each other in terms of their means. This difference increases the between-groups variance, as there is a larger spread between the group means.

Quiz 17: Statistical Reasoning: An Introduction

Inferential statistics are used to assess the importance of experimental results.

The Pearson product?moment correlation coefficient is referred to as

In comparison with one-tailed tests, two-tailed tests are

Simple analysis of variance is used in designs having

The Mann-Whitney U test is

In describing an array of data, psychologists typically present two descriptive statistics, the mean and the variance.

If a person's score is part of a normal distribution of scores, we can determine the relative rank of that score if we know

The larger the sample, the more we can trust the sample _ to be an estimate of the population _.

The Wilcoxon signed-ranks test

Which of the following is a parametric test?

The power of a statistical test refers to its ability to

The median is often used because it is insensitive to extreme scores.

Which of the following is NOT a measure of dispersion?

In a multifactor analysis of variance, how the variables affect one another is called

The inflection point in the normal curve is _____________ from the mean.

In a histogram, the values for the dependent variable are displayed on the ordinate (Y-axis) and the frequency with which each value of the dependent value occurred is displayed on the abscissa (X-axis).

In hypothesis testing, both the magnitude of the difference and the direction of the difference between two groups are considered in

The F statistic is

The number of participants in a study is denoted by

If experimental treatments produce an effect,