Quan 340

For a set of data, the mean is 50 and the standard deviation is 10. In the raw data, one of the observations is equal to 74 . After the data are standardized, what will be the standardized value of this observation? A. +-2.4 B. +7.4 C. -2.4 D. -7.4

+2.4

The largest value in a set of data is 160, and the smallest value is 70. If the resulting frequency distribution is to have six classes of equal width, what will be the class interval? A. 6 B. 12 C. 15 D. 5

15

A stem-and-leaf display describes two-digit integers between 20 and 80. For one of the classes displayed, the row appears as 5l246. What numerical values are being described? A. 60, 50, 40, and 20 B. 52, 54, and 56 C. 25, 45, and 65 D. 46 and 52

52, 54, 56

The averaging score for a class of 25 students was 75. If the 15 female students in the class averaged 70, then the male students in the class averaged: A. 82.5 B. 75.0 C. 85.0 D. 70.0 E. 77.5

82.5

The value in the data set that occurs with the greets frequency is know as the: A. Mode B. Median C. Variance D. Mean E. Weighted Mean

A Mode

A summary measure that is computed using the entire population is called A. Inferential Statistics B. A Sample C. A Parameter D. A Statistic

A Parameter

A summary measure that is computed from a sample to describe a characteristic of the population is called: A. A Statistic B. A Population C. A Parameter D. Inferential Statistic

A Statistic

In testing the significance of a multiple regression model in which there are three independent variables, the null hypothesis is:

A. H0: B1=B2=B3=0

In a positively skewed distribution, the: A. Mean is greater than the median and the median is greater than the mode B. Mean is smaller than the median and the median is smaller than the mode C. Mean is equal to the median and the median is equal to the mode D. Mean is greater than the median and the median is smaller than the mode E. mean is smaller than the median and the median is greater than the mode

A. Mean is greater than the median and the median is greater than the mode

The residual is defined as the difference between the: A. Actual value of x and the estimated value of x B. Actual value of x and the estimated value of y C. Actual value of y and the estimated value of y D. Actual value of y and the estimated value of x

Actual value of y and the estimated value of y

Which of the following techniques are applicable to quantitative data? A. Stem-and-leaf display B. Frequency Distributions C. The Data Array D. Scatter Diagram and dotplot E. All of these

All of these

Which of the following statements are true regarding the normal distribution curve? A. It is bell-shaped B. It is Symmetrical C. It is asymptotic in that each end approaches the horizontal axis, but never reaches it D. Its mean, median, and mode are located at the same position E. All of these statements are true

All of these statements are true

The difference between a histogram and a bar chart is that: A. The histogram reflects qualitative data while the bar chart represents quantitative data B. The adjacent rectangles in a histogram have a gap while those for a bar do not C. The histogram reflects quantitative data while the bar chart represents qualitative data D. the adjacent rectangles in a bar chart have a gap while those for a histogram do not.

C & D

The midway point between the upper and lower class limits for a frequency distribution is know as the A. Class Interval B. Class Average C. Class Mark D. Class Width E. Class Frequency

Class Mark

The midway point between the upper and lower class limits for a frequency distribution is know as the: A. Class Mark B. Class Average C. Class Frequency D. Class Width E. Class Interval

Class Mark

Which of the following statements is true regarding the normal distribution? A. The mean is less than the median and the median is less than the mode B. The mean is less than the mode, which in turn is less than the median C. The mean is greater than the mode, which in turn is greater than the median D. There is no difference in the values of the mean, median, and mode E. The mean in greater than the median and the median is greater than the mose

D. There is no difference in the values of the mean, median, and mode

When is a sample a better choice than a census A. When the population is changing over time B. When some sampling error can be tolerated C. When taking the U.S. Census of the population D. When time is an important factor E. Each of these is a reason for taking a sample rather than a census

Each of these is a reason for taking a sample rather than a census

If a set of events includes all the possible outcomes of an experiment, these events are considered to be: A. Mutually exclusive B. Exhaustive C. Intersecting D. Inclusive E. None of these choices

Exhaustive

Any normal distribution is a symmetrical, bell-shaped curve, with mean = 0 and standard deviation = 1.0 T/F

False

In a raw data listing, data are listed in increasing or decreasing numerical order T/F

False

In any normal distribution, the mean, median, mode, and standard deviation are all at the same position on the horizontal axis T/F

False

In the nominal measurement scale number represents "greater than" or "less than" measurements, such as rankings or preferences T/F

False

Interaction between two predictor variables is present when the effect on E(y) of a 1-unit increase in x2 does not depend on the value of x1 and vice versa T/F

False

It is a good idea to make point estimates based on x values that lie beyond the range of the underlying data T/F

False

Quantitive variables usually represent membership in groups or categories T/F

False

The Empirical Rule states that approximately 68% of the observations in any distribution will fall within one standard deviation of the mean. T/F

False

The mean of a set of values describes the 50th percentile. T/F

False

The simple linear regression model assumes that for any given value of x, the population of residuals will be normally distributed with a mean of zero and a standard deviation of 1. T/F

False

The union of events describes two or more events occurring at the same time. T/F

False

When a distribution has more values to the right and tails to the left, we say it is skewed positively. T/F

False

A continuous probability distribution represents a random variable: A. Having an infinite number of outcomes which may assume any number of values within an interval B. having outcomes, which occur in counting numbers. C. Which has a definite probability for the occurrence of a given integer D. which is best described in a histogram E. none of these is correct

Having an infinite number of outcomes which may assume any number of values within an interval

A continuous probability distribution represents a random variable: A. Which has definite probability for the occurrence of a give integer B. Having an infinite number of outcomes which may assume any number of values within an interval C. which is best described in a histogram D. having outcomes, which occur in counting numbers E. None of these is correct

Having an infinite number of outcomes which may assume any number of values within an interval

Regardless of the value of x, the standard deviation of the distribution of y values about the regression line is the same. This assumption of equal standard deviation about the regression line is called A. Pooled Variances B. Residual Analysis C. Heteroscedasticity D. Random Error E. Homoscedasticity

Homoscedasticity

Simple linear regression requires that the scales of measurement be expressed in either. A. Interval or Ratio B. Ordinal or Ratio C. Nominal or Raito D. Nominal or Interval E. Nominal or ordinal

Interval or Raito

simple linear regression requires that the scales of measurements be expressed in either: A. Nominal or Interval B. Nominal or Ordinal C. Nominal or Ratio D. Interval or Ratio E. Ordinal or Ratio

Interval or Ratio

The measure of central tendency that is most affected by extreme values is the: A. Mean B. Mode C. Range D. Median E. Coefficient of Variation

Mean

Which of the following is not a measure of central tendency? A. Arithmetic Mean B. Weighted Mean C. Mode D. Median E. Mean Absolute Deviation

Mean Absolute Deviation

When a person receives a mail questionnaire and places it in the wastebasket, they are contributing to: A. non sampling error B. nonresponse error C. response error D. nonsystematic error E. sampling error

Nonresponse Error

The adjusted multiple coefficient of determination is adjusted for the: A. Coefficient of correlation and the significance level B. Number of dependent variables and the sample size C. Number of regression parameters including the y-intercept D. Number of independent variables and the sample size

Number of independent variables and the sample size

The coefficient of correlation r is a number that indicates the: A. Strength of the relationship between the dependent variable y and the independent variable x B. Direction of the relationship between the dependent variable y and the independent variable x C. Proportion of the variation in the dependent variable y that is explained by the independent variable x D. Only direction of the relationship between the dependent variable y and the independent variable x and strength of the relationship between the dependent variable y and the independent variable x are correct E. Direction of the relationship between the dependent variable y and the independent variable x, strength of the relationship between the dependent variable y and the independent variable x, and proportion of the variation in the dependent variable y that is explained by the independent variable x are all correct

Only direction of the relationship between the dependent variable y and the independent variable x and strength of the relationship between the dependent variable y and the independent variable x are correct

For a given value of x, the estimation interval for an individual y observation is called the A. Least-squares interval B. Standard Error of Estimate C. Confidence Interval D. Prediction Interval E. Residual

Prediction interval

Another name for the residual term in a regression equation is A. Pooled Variances B. Random Error C. Residual analysis D. Homoscedasticity E. Heteroscedasticity

Random Error

The vertical spread of the data points about the regression line is measured by the A. homoscedasticity coefficient B. y-intercept C. Regression coefficient D. T-Ratio E. Standard error of estimate

Standard Error of Estimate

A characteristic of a sample, such as the sample mean or sample standard deviation, is known as a A. Population B. Census C. Parameter D. Statistic E. Observation

Statistic

Correlation analysis is used to determine the A.Coefficient of Determination B. Least squares estimates of the regression parameters C. Strength of the relationship between x an y D. Predicted value of y for a given value of x

Strength of the relationship between x an y

The measure of central tendency that is least affected by extreme value is the: A. The mean B. The variance C. The weighted mean D. The Median E. The Standard Deviation

The Median

Which of the following variables probably could be measured in an observational study of airlines travelers A. The total number of bags taken on the airplane trip B. The brand of coffee they drink at home C. The gender of the traveler D. The occupation of the traveler E. How many frequent traveler miles they have earned

The gender of the traveler

Which of the following statements is correct? A. The mode gives equal consideration to even very extreme values in the data. B. The mean is able to make the most complete use of the data when compared to the median and mode C. There will be just one value for the mean, median, and mode in the data set D. The median can be strongly influenced by just one or two very low or high values E. None of these chooses are correct

The mean is able to make the most complete use of the data when compared to the median and mode

Which of the following is not a characteristic for a normal distribution A. It is symmetrical distribution B. The mean, median, and mode are all equal C. It is a bell-shaped distribution D. The mean is always zero E. the area under the curve always equals 1.0

The mean is always zero

Which of the following are not correct concerning the probability distribution for any continuous random variable A. The range of the random variable is found on the y-axis B. The area under the curve represents the sum of probabilities for all possible outcomes C. The probability that x will take on a value between a and b will be the area under the curve between points a and b D. The vertical coordinate is the probability density function E. The total area represented under the curve will be equal to 1.00

The range of the random variable is found on the y-axis

Which of the following statements is correct? A. The standard deviation is a measure of dispersion B. The variance is a measure of central tendency C. The range is a measure of central tendency D. The mean is a measure of the deviation in a data set E. The median is a measure of dispersion

The standard deviation is a measure of dispersion

A qualitive variable such as gender can be included in regression analysis and is referred to as a dummy variable T/F

True

Business Statistics can be described as the collection, summarization, analysis, and reporting of numerical findings relative to a business decision or situation T/F

True

Characteristics of the population are referred to as parameters, while characteristics of the sample are referred to as statistics. T/F

True

In practice, most studies involve relatively large populations for which taking a sample can provide satisfactory results much more quickly and at considerably lower cost than a census

True

Statistics can be used as a descriptive tool for expressing information relevant to business T/F

True

Statistics can be used as an inferential device for using sample findings to draw conclusions about a population T/F

True

The coefficient of determination can be described in terms of the total variation in y versus the unexplained variation in y T/F

True

The first-order polynomial model is the same as the simple linear regression model T/F

True

The population is sometimes referred to as the universe and is the entire set of people or objects of interest T/F

True

The standard normal distribution has a mean of 0.0 and standard deviation of 1.0 T/F

True

The standard normal distribution has a mean of 0.0 and standard deviation of 1.0 T/F

True

There are two key variables in an experiment: the independent variable ( or treatment) and the dependent variable ( or measurement)

True

There exists a different normal curve for every possible pair of Mean and Standard Deviation T/F

True

Uncertainty plays an important role in our daily lives and activities as well as in business. T/F

True

Under certain conditions, the normal distribution can be used to approximate the binomial distribution T/F

True

When the events within a set are both mutually exclusive and exhaustive, the sum of their probabilities is 1.0 T/F

True

Which of the following is not a measure of dispersion? A. Quantiles B. Mean Absolute Deviation C. Range D. Weighted Mean E. Standard Deviation

Weighted Mean

Chebyshev's Theorem states that the percentile of observations in a data set that should fall within five standard deviations of their mean is: A. at least 96% B. 25% C. at least 90% D. 96% E. 90%

at least 96%

In simple linear regression, the coefficient of correlation r and the last squares estimate b1 of the population slope b1: A. Must have the same sign B. May have opposite signs or the same sign C. must have the same numerical value D. Must have opposite signs

must have the same sign

The class interval is the: A. number of data values falling within each class B. lower and upper limits of each class C. width of each class D. number of categories of the frequency distribution E. mid-point of each class

width of each class