BANA 2 Midterm 1 Prep
What would be the coefficient of determination if the total sum of squares (SST) is 23.29 and the sum of squares due to regression (SSR) is 10.03?
.43
The scatter chart in the file below displays the residuals versus the dependent variable, x. Which of the following conclusions can be drawn from this scatter chart?
The residuals have an increasing variance as the dependent variable increases.
What is the difference between the observed value of the dependent variable and the value predicted using the estimated regression equation?
residual
A _____ is a graphical presentation of the relationship between two quantitative variables.
scatter chart
_____ refers to the use of sample data to calculate a range of values that is believed to include the value of the population parameter.
Interval estimation
Which of the following analytical techniques helps us arrive at the best decision?
Prescriptive
Which of the following analytical techniques helps us arrive at the best decision?
Prescriptive analytics
Use the applet "Least-Squares Best Fit for Estimating Regression Line" to answer the following questions. Drag the end of the blue line on the scatter diagram up and down. How does the position of the line relate to the value of r-squared on the left?
The better the line fits the data the higher the value of r-squared.
When the mean value of the dependent variable is independent of variation in the independent variable, the slope of the regression line is _____.
Zero
The groups g = 0 and g = 1 correspond to the values of the variable x1 = 0 and x1 = 1, respectively. That is, the line for g = 0 is the graph of the regression equation with 0 in place for x1, while the line for g = 1 is the graph of the regression equation with 1 in place for x1. Set all of the sliders to 0, then set b3 = 1. Now move the slider for b1 back and forth. Observe how this affects the y-intercept for each line. Set the slider for b1 = 1. Which of the following sets of equations describes the lines g = 0 and g = 1?
g = 0: y = 0 g = 1: y = 1 + x2
The process of making estimates and drawing conclusions about one or more characteristics of a population through analysis of sample data drawn from the population is known as _____
statistical inference
The graph of the simple linear regression equation is a(n) _____.
straight line
Next, hit the "Find Best Line" button and then the "Display/Hide Error Squares" button. Move the line up and down a few times. What does the total area of the orange squares represent?
sum of squares due to error (SSE)
The company identified in Chapter 7, Analytics in Action, is
Wallmart.com
A two-dimensional graph representing the data using different shades of color to indicate magnitude is called a _____.
heat map
What would be the value of the sum of squares due to regression (SSR) if the total sum of squares (SST) is 25.32 and the sum of squares due to error (SSE) is 6.89?
18.43
To include education in a regression model where education is defined as: did not graduate high school, high school graduate, some college, undergraduate degree, at least one graduate degree, the number of dummy variables required is
4
_____ is used to test the hypothesis that the values of the regression parameters β1, β2, ... βq are all zero.
An F Test
Which of the following best exemplifies big data?
Cellphone owners around the world generate vast amounts of data by calling, texting, tweeting, and browsing the Web on a daily basis.
_____ are visual methods of displaying data.
Charts
The company identified in Chapter 3, Analytics in Action, is
Cincinnati Zoo & Botanical Garden
Data dashboards are a type of _________ analytics.
Descriptive
refers to the scenario in which the relationship between the dependent variable and one independent variable is different at different values of a second independent variable.
Interaction
refers to the technology that allows data, collected from sensors in all types of machines, to be sent over the Internet to repositories where it can be stored and analyzed.
Internet of Things (IoT)
The ratio of the amount of ink used in a table or chart that is necessary to convey information to the total amount of ink used in the table and chart is known as data-ink ratio. Using additional ink that is not necessary to convey information has what effect on the data-ink ratio?
It reduces the data-ink ratio.
Which one of the following is used in predictive analytics?
Linear regression
_____ refers to the degree of correlation among independent variables in a regression model.
Multicollinearity
If you were thinking about opening up several new pizza places near colleges with 20,000 students, would you feel 95% confident that mean sales for those stores would be $175,000?
No
To summarize and analyze data with both a crosstabulation and charting, Excel typically pairs _____.
PivotCharts with PivotTables
______________ analytics are techniques that use models, constructed from past data, to predict the future or to ascertain the impact of one variable on another.
Predictive
Which of the following regression models is used to model a nonlinear relationship between the independent and dependent variables by including the independent variable and the square of the independent variable in the model?
Quadratic regression model
Use the applet "Confidence Interval for the Mean Value of y" to answer the following questions. The best/most precise estimate of the mean value of y is located at the mean of the x values. TrueFalse
True
A data visualization tool that updates in real time and gives multiple outputs is called _____.
a data dashboard
The Analytics in Action example in Chapter 3 concerned
a data dashboard.
A variable used to model the effect of categorical independent variables in a regression model which generally takes only the value zero or one is called _____.
a dummy variable
In order to visualize three variables in a two-dimensional graph, we use a _____.
bubble chart
Use the applet "Regression Analysis: Interactions" to answer the following questions. Experiment with each slider. Set the sliders to different values and observe the effect on the slopes of the regression lines. Try to make the two lines parallel. Which slider do you need to use to make the lines have the same slope?
b^3
The charts that are helpful in making comparisons between categorical variables are _____.
bar charts and column charts
The _____ is a measure of the goodness of fit of the estimated regression equation. It can be interpreted as the proportion of the variability in the dependent variable y that is explained by the estimated regression equation.
coefficient of determination
Chapter 3 focuses on
data visualization
When a decision maker is faced with several alternatives and an uncertain set of future events, s/he uses _____ to develop an optimal strategy.
decision analysis
In the simple linear regression model, the _____ accounts for the variability in the dependent variable that cannot be explained by the linear relationship between the variables.
error term
Consider the attached clustered bar chart of the dashboard developed to monitor the performance of a call center. This chart allows the IT manager to _____.
identify the frequency of a particular type of problem by location
In a linear regression model, the variable (or variables) used for predicting or explaining values of the response variable are known as the _____. It(they) is(are) denoted by x.
independent variable
Data-ink is the ink used in a table or chart that _____.
is necessary to convey the meaning of the data to the audience
In a business, the values indicating the businesss current operating characteristics, such as its financial position, the inventory on hand, and customer service metrics, are typically known as
key performance indicators
The prespecified value of the independent variable at which its relationship with the dependent variable changes in a piecewise linear regression model is referred to as the ______.
knot
The attached image is a _____.
line chart
Chapter 7 focuses on
linear regression
Regression analysis involving one dependent variable and more than one independent variable is known as ____.
multiple regression
Advanced analytics generally refers to _____.
predictive and prescriptive analytics
Making visual comparisons between categorical variables may be difficult in a _____.
pie chart
In a simple linear regression model, y = β0 + β1x + ε the parameter β1 represents the _____.
slope of the true regression line
A line chart that has no axes but is used to provide information on overall trends for time series data is called a _____.
sparkline
The least squares regression line minimizes the sum of the _____
squared differences between actual and predicted y values
Tables should be used instead of charts when _____.
the values being displayed have different units or very different magnitudes
A _____ is a line that provides an approximation of the relationship between the variables.
trendline
The Analytics in Action example in Chapter 7 concerned
managing packaging of orders.
In a linear regression model, the variable that is being predicted or explained is known as _____. It is denoted by y and is often referred to as the response variable.
dependent variable
Deleting the grid lines in a table and the horizontal lines in a chart ______.
increases the data-ink ratio
In the financial sector, _____ are used to construct financial instruments such as derivatives.
predictive models