Warning: foreach() argument must be of type array|object, bool given in /var/www/html/web/app/themes/studypress-core-theme/template-parts/header/mobile-offcanvas.php on line 20

Prey attracts predators . Here is computer output from the least-squares regression analysis of the perch data

a. What is the estimate for β0? Interpret this value.

b. What is the estimate for β1? Interpret this value.

c. What is the estimate for σ? Interpret this value.

d. Give the standard error of the slope SEb1. Interpret this value.

Short Answer

Expert verified

a. When the number of perch in the pen is zero, the proportion of perch killed is on average 0.12049.

b. On average, the proportion of perch killed increases by 0.008569per beer.

c. The projected proportion of perch killed differs from the actual proportion of perch killed by 0.1886on average.

d. The slope of the regression line differs from the slope of the population regression line by around 0.002456on average.

Step by step solution

01

Part (a) Step 1 : Given information

We have to find the estimate for β0, explain this value.

02

Part (a) Step 2 : Simplification

b0Corresponding0to the y intercepting the population regression line, which may be approximated using the sample regression line's y intercept .
b0=0.12049
When x=0, the y-intercept shows the average value of y.
When the number of perch in the pen is zero, the proportion of perch killed is on average 0.12049.
03

Part (b) Step 1 : Given information

We have to find the estimate for β1, explain this value.

04

Part (b) Step 2 : Simplification

The slope of the population regression line can be determined using the slope of the b1of the sample regression line.
b1=0.008569
The average rise in y per unit of x is represented by slope.
On average, the proportion of perch killed increases by0.008569 per beer.
05

Part (c) Step 1 : Given information

We have to find the estimate for σ, explain this value.

06

Part (c) Step 2 : Simplification

The sample standard deviation of the residuals sis used to determine the population standard deviation of the residual.
s=0.1886
The standard error of the estimate srepresents the average prediction error, and thus the average deviation between actual and expected y values.
The projected proportion of perch killed differs from the actual proportion of perch killed by 0.1886on average.
07

Part (d) Step 1 : Given information

We have to find the standard error of the slope SEb1, explain this value.

08

Part (d) Step 2 : Simplification

In the row "Perch" and the column "stdev." of the mentioned computer output, the standard error of the slope SEb1 is mentioned.
SEb1=0.002456
The average divergence of the slope of the sample regression line from the population regression line of the slope is shown by the standard error of the slope.
The slope of the regression line differs from the slope of the population regression line by around 0.002456on average.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A large machine is filled with thousands of small pieces of candy, 40%of which are orange. When money is deposited, the machine dispenses60randomly selected pieces of candy. The machine will be recalibrated if a group of 60candies contains fewer than18that are orange. What is the approximate probability that this will happen if the machine is working correctly?

a. P(z<0.30.4(0.4)(0.6)60)Pz&1t;0.3-0.4(0.4)(0.6)60

b.P(z<0.30.4(0.3)(0.7)60)Pz&1t;0.3-0.4(0.3)(0.7)60

d. P(z<0.3-0.4(0.4)(0.6)60)Pz&lt;0.3-0.4(0.4)(0.6)60

c. P(z<0.3-0.4(0.4)(0.6)60)

Pz&lt;0.3-0.4(0.4)(0.6)60

e. P(z<0.4-0.3(0.3)(0.7)60)Pz&lt;0.4-0.3(0.3)(0.7)60

Women who are severely overweight suffer economic consequences, a study has shown. They have household incomes that are $6710less than other women, on average. The findings are from an eight-year observational study of 10,039randomly selected women who were 16-24years old when the research began. If the difference in average incomes is statistically significant, does this study give convincing evidence that being severely overweight causes a woman to have a lower income?

a. Yes; the study included both women who were severely overweight and women who were not.

b. Yes; the subjects in the study were selected at random.

c. Yes, because the difference in average incomes is larger than would be expected by chance alone.

d. No; the study showed that there is no connection between income and being severely overweight.

e. No; the study suggests an association between income and being severely overweight, but we can’t draw a cause-and-effect conclusion.

Two six-sided dice are rolled and the sum of the faces showing is recorded after each roll. Let X=the number of rolls required to obtain a sum greater than 7. If 100trials are conducted, which of the following is most likely to be the result of the simulation?

a.

b.

c.

d.

e.

In a recent poll, randomly selected New York State residents at various fast-food restaurants were asked if they supported or opposed a "fat tax" on sugared soda. Thirtyone percent said that they were in favor of such a tax and 66% were opposed. But when asked if they would support such a tax if the money raised were used to fund health care given the high incidence of obesity in the United States, 48% said that they were in favor and 49% were opposed.
(a) In this situation, explain how bias may have been introduced based on the way the questions were worded and suggest a way that the questions could have been worded differently in order to avoid this bias.
(b) In this situation, explain how bias may have been introduced based on the way the sample was taken and suggest a way that the sample could have been obtained in order to avoid this bias.
(c) This poll was conducted only in New York State. Suppose the pollsters wanted to ensure that estimates for the proportion of people who would support a tax on sugared soda were available for each state as well as an overall estimate for the nation as a whole. Identify a sampling method that would achieve this goal and briefly describe how the sample would be taken.

A scatterplot of yversus xshows a positive, nonlinear association. Two different transformations are attempted to try to linearize the association: using the logarithm of the y-values and using the square root of the y-values. Two least-squares regression lines are calculated, one that uses x to predict log(y) and the other that uses x to predict y. Which of the following would be the best reason to prefer the least-squares regression line that uses x to predict log(y)?

a. The value of r2is smaller.

b. The standard deviation of the residuals is smaller.

c. The slope is greater.

d. The residual plot has more random scatter.

e. The distribution of residuals is more Normal.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free