Multiple choice 1

An example of manipulating a graphical display to distort reality is ___________. starting the axes at zero stretching the axes starting the axes at zero and stretching the axes making the bars in a histogram equal widths

stretching the axes

If the Durbin-Watson statistic is less than dL, then we conclude that the test results are inconclusive. there is significant positive autocorrelation. there is significant negative autocorrelation. there is significant autocorrelation, but we cannot identify whether it is positive or negative.

there is significant positive autocorrelation

Which of the following is the best analytic dashboard graphical method for visualizing hierarchical information? bullet graph sparkline treemap gauge

treemap

A Stem-and-leaf display is best used to ___________. provide a point estimate of the variability of the data set display the shape of the distribution None of the other choices is correct. provide a point estimate of the central tendency of the data set

display the shape of the distribution

A data set provides information about some group of individual _____________. measurements variables elements statistics

elements

All of the following are assumptions of the error terms in the simple linear regression model except: errors are normally distributed. error terms have a mean of zero. error terms are dependent on each other. error terms have a constant variance.

error terms are dependent on each other

The _____________ is the range of the previously observed values of x. population region slope experimental region coefficient of determination

experimental region

In simple regression analysis, the quantity E(Y-Y)^2 is called the __________ sum of squares. unexplained explained error total

explained

A population that consists of all the customers who will use the drive-thru of the local fast food restaurant is called a(n) _____________. statistical population random sample population finite population infinite population

finite population

When the assumption of __________ residuals (error terms) is violated, the Durbin-Watson statistic is used to test to determine if there is significant _____________ among the residuals. normality, autocorrelation independent, autocorrelation normality, probability independent, probability

independent, autocorrelation

A person's telephone area code is an example of a(n) _____________ variable. ordinal nominative interval ratio

nominative

If successive values of the residuals are close together, then there is a ___________ autocorrelation and the value of the Durbin-Watson statistic is _________. negative, small positive, small positive, large negative, large

positive, small

As a measure of variation, the sample ___________ is easy to understand and compute. It is based on the two extreme values and is therefore a highly unstable measure. range standard deviation interquartile range coefficient of variation variance

range

The Durbin-Watson test statistic ranges from −4 to 4. 0 to 4. 0 to 1. 0 to 3. −1 to 1.

0 to 4

What value of the Durbin-Watson statistic indicates that there is no autocorrelation present in time-ordered data? 2 −2 1 0 −1

2

In a statistics class, 10 scores were randomly selected with the following results (mean = 71.5): 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the standard deviation? 4.77 12.00 144.00 22.72 516.20

4.77

The number of items rejected daily by a manufacturer because of defects for the last 30 days are: 20, 21, 8, 17, 22, 19, 18, 19, 14, 17, 11, 6, 21, 25, 4, 19, 9, 12, 16, 16, 10, 28, 24, 6, 21, 20, 25, 5, 17, 8 How many classes should be used in constructing a histogram? 6 5 8 7 4

5

The change in the daily price of a stock is what type of variable? quantitative ordinal random qualitative

quantitative

______________ and _____________ are used to describe qualitative (categorical) data. Scatter plots, histograms Stem-and-leaf displays, scatter plots Pie charts, histograms Bar charts, pie charts Box plots, bar charts

Bar charts, pie charts

When the constant variance assumption holds, a plot of the residual versus x? fans out, but then funnels in. funnels in. fans out. suggests an increasing error variance. forms a horizontal band pattern.

Forms a horizontal band pattern

The ___________ the r2 and the __________ the s (standard error), the stronger the relationship between the dependent variable and the independent variable. higher, higher lower, lower lower, higher higher, lower

Higher, lower

A graphical portrayal of a quantitative data set that divides the data into classes and gives the frequency of each class is a(n) ___________. histogram bar chart dot plot ogive plot Pareto chart

Histogram

The _____ distribution is used for testing the significance of the slope term. t r2 z r

t

___________ sampling is where we know the chance that each element will be included in the sample, which allows us to make statistical inferences about the sample population. Judgment Convenience Voluntary Probability

Probability

A(n) ____________ variable can have values that indicate into which of several categories of a population it belongs. qualitative ratio interval quantitative

Qualitative

The simple linear regression (least squares method) minimizes total variation. SSyy. the explained variation. SSxx. SSE.

SSE

A ______________ shows the relationship between two variables. stem-and-leaf bar chart histogram pie chart scatter plot

Scatter plot

The least squares regression line minimizes the sum of the? squared differences between actual and predicted X values. absolute deviations between actual and predicted Y values. differences between actual and predicted Y values. absolute deviations between actual and predicted X values. squared differences between actual and predicted Y values.

Squared differences between actual and predicted Y values

A flaw possessed by a population or sample unit is ___________. a defect the cause for extreme skewness to the right displayed by a dot plot always random

a defect

In a simple linear regression model, the slope term is the change in the mean value of y associated with _____________ in x. a corresponding increase a variable change a one-unit increase no change

a one unit increase

Which of the following is a violation of the independence assumption? positive autocorrelation negative autocorrelation a pattern of alternating error terms over time a pattern of cyclical error terms over time All of the other choices are correct.

all are correct

The general term for a graphical display of categorical data made up of vertical or horizontal bars is called a(n) ___________. pie chart ogive plot Pareto chart bar chart

bar chart

As a general rule, when creating a stem-and-leaf display, there should be ______ stem values. between 5 and 20 no fewer than 20 between 3 and 10 between 1 and 100

between 5 and 20

Which of the following is not a method of predictive analytics? outlier detection association learning bullet graphs factor detection

bullet graphs

Examining all population measurements is called a_____________. variable census frame sample

census

The ______________ is a quantity that measures the variation of a population or sample relative to its mean. Z-score mean coefficient of variation range standard deviation

coefficient of variation

The ____________ assumption requires that all variation around the regression line should be equal at all possible values (levels) of the ___________variable. constant variance, independent constant variance, dependent control variance, dependent control variance, independent

constant variance, independent

The _____________ measures the strength of the linear relationship between the dependent variable and the independent variable. distance value residual Y-intercept correlation coefficient

correlation coefficient

Which of the following is a measure of the strength of the linear relationship between x and y that is dependent on the units in which x and y are measured. covariance least squares line slope correlation coefficient

covariance

___________ refers to describing the important aspects of a set of measurements. Cross-sectional analysis Descriptive statistics Time series analysis Runs plot

descriptive statistics

Which of the following is not a supervised learning technique in predictive analytics? linear regression decision trees neural networks factor analysis

factor analysis

The number of measurements falling within a class interval is called the ___________. relative frequency leaf frequency cumulative sum

frequency

Which one of the following graphical tools is used with quantitative data? Pareto chart histogram pie chart bar chart

histogram

If there is significant autocorrelation present in a data set, the ________________ assumption is violated. μ = 0 constant variation independence of error terms normality

independence of error terms

Statistical ____________ refers to using a sample of measurements and making generalizations about the important aspects of a population. sampling inference process analysis

inference

Temperature (in degrees Fahrenheit) is an example of a(n) __________ variable. interval nominative ordinal ratio

interval

Any value of the error term in a regression model _____________ any other value of the error term. is independent of is exactly the same as increases with is dependent on

is independent of

When using simple linear regression, we would like to use confidence intervals for the ___________ and prediction intervals for the ___________ at a given value of x. mean y-value, individual y-value Individual y-value, mean y-value slope, mean slope y-intercept, mean y-intercept

mean y value, individual y value

Another name for the 50th percentile is the ___________. first quartile third quartile median mean mode

median

The point estimate of the variance in a regression model is SSE. b0. b1. MSE.

mse

In simple regression analysis, the standard error is ___________ greater than the standard deviation of y values. never sometimes always

never

__________ is a necessary component of a runs plot. Random sampling of the data Cross-sectional data Observation over time Qualitative variable

observation over time

Measurements from a population are called? variables. observations. processes. elements.

observations

An identification of police officers by rank would represent a(n) ____________ level of measurement. nominative ordinal ratio interval

ordinal

A set of all elements we wish to study is called a ____________. population process census sample

population

A ____________ variable can have values that are numbers on the real number line. nominative qualitative quantitative categorical

quantitative

One method of determining whether a sample being studied can be used to make statistical inferences about the population is to? run a descriptive statistical analysis. create a cross-sectional data analysis. produce a runs plot. calculate a proportion.

produce a runs plot

If one of the assumptions of the regression model is violated, performing data transformations on the ____________ can remedy the situation. independent variable response variable slope predictor variable

response variable

The point estimate of the _______________ is the positive square root of the sample variance. median sample standard deviation population standard deviation range sample mean

sample standard deviation

When we are choosing a random sample and we do not place chosen units back into the population, we are? sampling with replacement. using a systematic sample. sampling without replacement. using a voluntary response sample.

sampling without replacement

Data collected for a particular study are referred to as a data ____________. set variable measurement element

set

A relative frequency curve having a long tail to the right is said to be ___________. skewed to the left skewed to the right normal a scatter plot

skewed to the right

After plotting the data points on a scatter diagram, we have observed an inverse relationship between the independent variable (X) and the dependent variable (Y). Therefore, we can expect both the sample ___________ and the sample _____________ to be negative values. intercept, correlation coefficient slope, correlation coefficient slope, standard error of estimate slope, coefficient of determination intercept, slope

slope, correlation coefficient

If we collect data on the number of wins the Dallas Cowboys earned each of the past 10 years, we have _____________ data. cross-sectional survey time series non-historical

time series

Which of the following is not an example of unethical statistical practices? descriptive measures that mislead the user using graphs to make statistical inferences inappropriate interpretation of statistical results None of the other answers is correct. improper sampling

using graphs to make statistical inferences

Any characteristic of a population unit is a(n) variable. sample. measurement. observation.

variable

Which of the following is a categorical variable? daily sales in a store air temperature whether a person has a traffic violation bank account balance value of company stock

whether a person has a traffic violation

The ___________ of the simple linear regression model is the value of y when the mean value of x is zero. independent variable y-intercept response variable slope

y intercept