Question 1

Create a model to predict postal rates from the year.

Accepted Answer

Dependent variable is: Postal

Question 2

Explain the meaning of } R 2 in the context of this problem.

Accepted Answer

@#LAT-DLM&. So @#LAT-DLM& of the variation in diam

Question 3

Explain the meaning of R 2 in the context of this problem.

Accepted Answer

Question 4

A company studying the productivity of its employees on a new information system was interested in determining if the age $( X )$ of data entry operators influenced the number of completed entries made per hour (Y). The regression equation is $\hat { y } = 14.374 - 0.145 x$.
Suppose the actual completed entries per hour for an operator who is 35 years old was 8 . The residual is

Accepted Answer

A)  $- 1.3$ 
B)  $2.6$ 
C)  $- 3.5$ 
D)  $1.3$ 
E)  $- 2.2$ 
A)  $- 1.3$ 
B)  $2.6$ 
C)  $- 3.5$ 
D)  $1.3$ 
E)  $- 2.2$

Question 5

An 8th grade class develops a linear model that predicts the number of cheerios (a small round cereal) that fit on the circumference of a plate by using the diameter in inches. Their model is${\hat{\text { cheerios }}}$ $= 0.56 + 5.11$ (diameter).
The slope of this model is best interpreted in context as...

Accepted Answer

A)  For every $5.11$ inches of diameter, the circumference is about 1 cheerio bigger. 
B)  For every 1 inch of diameter, the circumference holds about $0.56$ more cheerios. 
C)  It takes $5.11$ cheerios to fill a plate's circumference. 
D)  For every 1 inch of diameter, the circumference holds about $5.11$ more cheerios. 
E)  A mistake, because $\pi$ is about $3.14$ and that should be the slope. 
A)  For every $5.11$ inches of diameter, the circumference is about 1 cheerio bigger. 
B)  For every 1 inch of diameter, the circumference holds about $0.56$ more cheerios. 
C)  It takes $5.11$ cheerios to fill a plate's circumference. 
D)  For every 1 inch of diameter, the circumference holds about $5.11$ more cheerios. 
E)  A mistake, because $\pi$ is about $3.14$ and that should be the slope.

Question 6

Interpret the intercept of your model in context.

Accepted Answer

Intercept of the model is -19.

Question 7

A company studying the productivity of their employees on a new information system was interested in determining if the age $( X )$ of data entry operators influenced the number of completed entries made per hour (Y). The regression equation is $\hat { y } = 14.374 - 0.145 x$. If $s _ { x } = 14.04$ and $s _ { y } = 2.61$, then the correlation coefficient between age and productivity is

Accepted Answer

A)  $.779$ 
B)  $- .236$ 
C)  $.575$ 
D)  $- .929$ 
E)  $- .779$ 
A)  $.779$ 
B)  $- .236$ 
C)  $.575$ 
D)  $- .929$ 
E)  $- .779$

Question 8

What is the correlation between cost and size?

Accepted Answer

The correlation, @#LAT-DLM&, is @#LAT-DLM&. Since

Question 9

Residuals are …

Accepted Answer

A) the difference between observed responses and values predicted by the model. 
B) data collected from individuals that is not consistent with the rest of the group. 
C) none of these 
D) possible models not explored by the researcher. 
E) variation in the data that is explained by the model. 
A) the difference between observed responses and values predicted by the model. 
B) data collected from individuals that is not consistent with the rest of the group. 
C) none of these 
D) possible models not explored by the researcher. 
E) variation in the data that is explained by the model.

Question 10

It's easy to measure the circumference of a tree's trunk, but not so easy to measure its height. Foresters developed a model for ponderosa pines that they use to predict the tree's height (in feet) from the circumference of its trunk (in inches): $\ln \hat { h } = - 1.2 + 1.4 ( \ln C$ ). A lumberjack finds a tree with a circumference of $60 "$; how tall does this model estimate the tree to be?

Accepted Answer

A)  11' 
B)  $83 ^ { \prime }$ 
C)  $93 ^ { \prime }$ 
D)  19' 
E)  $5 ^ { \prime }$ 
A)  11' 
B)  $83 ^ { \prime }$ 
C)  $93 ^ { \prime }$ 
D)  19' 
E)  $5 ^ { \prime }$

Create a model to predict postal rates from the year.

Explain the meaning of } R ² in the context of this problem.

Explain the meaning of R ² in the context of this problem.

Interpret the intercept of your model in context.

What is the correlation between cost and size?

Residuals are …

Stats Starts Here

Displaying and Describing Data

Relationships Between Categorical Variablescontingency Tables

Understanding and Comparing Distributions

The Standard Deviation As a Ruler and the Normal Model

Scatterplots, Association, and Correlation

Regression Wisdom

Multiple Regression

Sample Surveys

Experiments and Observational Studies

From Randomness to Probability

Sampling Distribution Models and Confidence Intervals for Proportions

Confidence Intervals for Means

Testing Hypotheses

More About Tests and Intervals

Comparing Groupspaired

Samples and Blocks

Comparing Counts

Filters

Exam 7: Linear Regression

Create a model to predict postal rates from the year.

Explain the meaning of } R 2 in the context of this problem.

Explain the meaning of R 2 in the context of this problem.

Interpret the intercept of your model in context.

What is the correlation between cost and size?

Residuals are …

Stats Starts Here

Displaying and Describing Data

Relationships Between Categorical Variablescontingency Tables

Understanding and Comparing Distributions

The Standard Deviation As a Ruler and the Normal Model

Scatterplots, Association, and Correlation

Regression Wisdom

Multiple Regression

Sample Surveys

Experiments and Observational Studies

From Randomness to Probability

Sampling Distribution Models and Confidence Intervals for Proportions

Confidence Intervals for Means

Testing Hypotheses

More About Tests and Intervals

Comparing Groupspaired

Samples and Blocks

Comparing Counts

Filters

Explain the meaning of } R ² in the context of this problem.

Explain the meaning of R ² in the context of this problem.