Bird colonies One of nature’s patterns connects the percent of adult birds in a colony that return from the previous year and the number of new adults that join the colony. Here are data for 13colonies of sparrow-hawks:4

(a) Describe the direction, form, and strength of the relationship between number of new sparrow-hawks in a colony and percent of returning adults.

(b) For short-lived birds, the association between these variables is positive: changes in weather and food supply drive the populations of new and returning birds up or down together. For long-lived territorial birds, on the other hand, the association is negative because returning birds claim their territories in the colony and don’t leave room for new recruits. Which type of species is the sparrow-hawk? Explain.

Short Answer

Expert verified

(a) The direction, form, and strength are Negative, Linear, and Moderate.

(b) Long-lived territorial birds.

Step by step solution

01

Part(a) Step 1: Given Information 

From Exercise 6we get graph as

02

Part(a) Step 2: Explanation 

Direction: Because the scatterplot slopes downhill, the direction is negative.

Form: Because the scatterplot lacks curvature and the points appear to nearly lie on a line, the form is linear.

Strength: Moderate, due to the distance between the spots, although the linear pattern is visible.

03

Part(b) Step 1: Given Information 

From Exercise, 6we get graph as

04

Part(b) Step 2: Explanation 

Direction: Because the scatterplot slopes downhill, the direction is negative.

Because the variables have a negative correlation, we may deduce that the birds are long-lived territorial birds.

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

Bird colonies Return to the data of Exercise 53 on sparrow hawk colonies. We’ll use these data to illustrate influence.

(a) Make a scatterplot of the data suitable for predicting new adults from the percent of returning adults. Then add two new points. Point A: 10% return, 15

new adults. Point B: 60% return, 28 new adults. In which direction is each new point an outlier?

(b) Add three least-squares regression lines to your plot: for the original 13 colonies, for the original colonies plus Point A, and for the original colonies

plus Point B Which new point is more influential for the regression line? Explain in simple language why each new point moves the line in the way your graph shows.

Predicting tropical storms William Gray heads the Tropical Meteorology Project at Colorado State

University. His forecasts before each year’s hurricane 2008season attract lots of attention. Here are data on the number of named Atlantic tropical storms predicted by Dr. Gray and the actual number of storms for the years 1984 to 2008:

Analyze these data. How accurate are Dr. Gray’s forecasts? How many tropical storms would you expect in a year when his preseason forecast calls for 16 storms? What is the effect of the disastrous 2005 season on your answers? Follow the four-step process.

You have data for many years on the average price of a barrel of oil and the average retail price of a gallon of unleaded regular gasoline. If you want to see how well the price of oil predicts the price of gas, then you should make a scatterplot with ______ as the explanatory variable.

(a) the price of oil

(b) the price of gas

(c) the year

(d) either oil price or gas price

(e) time

Data on dating Refer to Exercise 20.

(a) How would r change if all the men were 6 inches shorter than the heights given in the table? Does the correlation tell us if women tend to date men taller than themselves?

(b) If heights were measured in centimeters rather than inches, how would the correlation change? (There are 2.54centimeters in an inch.)

Beavers and beetles Do beavers benefit beetles? Researchers laid out 23 circular plots, each 4 meters in diameter, in an area where beavers were cutting down cottonwood trees. In each plot, they counted the number of stumps from trees cut by beavers and the number of clusters of beetle larvae. Ecologists think that the new sprouts from stumps are more tender than other cottonwood growth, so beetles prefer them. If so, more stumps should produce more beetle larvae. Here are the data:

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