In this lesson, we will use a scatterplot and a regression line to solve the following problem. 

The Problem

The Table 1 below lists the estimated numbers in millions of airline passengers at some of the fastest growing airports in 1992 and 2005.   (Source: Federal Aviation Administration.)

Raleigh-Durham International had 4.9 million passengers in 1992.   Assuming Raleigh-Durham International follows the same trend in growth as the other airports reported in Table 1 below, estimate the number of passengers it may have in 2005.  Compare this result with the Federal Aviation Administration estimation of 10.3 million passengers.


   TABLE 1        Airline Passengers (in millions)
1992 2005
Harrisburg International 0.7 1.4
Dayton International 1.1 2.4
Austin Robert Mueller 2.2 4.7
Milwaukee General Mitchell 2.2 4.4
Sacramento Metropolitan 2.6 5.0
Fort Lauderdale-Hollywood 4.1 8.1
Washington Dulles 5.3 10.9
Greater Cinninnati 5.8 12.3

In order to solve this problem, we will:

a). Make a scatterplot of the data using the 1992 data for X-values and the corresponding 2005 data for Y-values. Predict whether the correlation coefficient will be positive or negative.

b). Find the least-squares regression line.

Then the results will be used to make the estimate of the number of passengers in 2005 for the Raleigh-Durham International Airport.

© 2001-2007, Macon State College.  All rights reserved.