A survey about a new bus route

Name: ______________________ Date: ____________ A survey about a new bus route (10 points)

Table

A city’s transit agency is planning a new express bus route. The city has four districts, A, B, C and D, and the agency has a complete list of the 48,000 home addresses in the city, organized by district (12,000 in each district). Residents of districts near the planned route may feel very differently about it from residents of districts far from it. The agency considers two ways to gather opinions:

Method 1: choose 100 addresses at random from each district’s list and interview one adult at each address.
Method 2: post a link on the agency’s website and social media asking residents to vote for or against the new route.

(a) Write an investigative question that the agency could answer with data from Method 1. [2 points]
(b) Identify the sampling method used in Method 1, and explain one statistical advantage of it over a simple random sample of 400 addresses from the whole city, in context. [3 points]
(c) Identify a source of bias in Method 2, and explain how it would likely affect the estimate of the proportion of residents who support the route. [2 points]
(d) Describe how to use a random number generator to select the 100 addresses from district A’s list of 12,000 addresses, so that someone else could follow your procedure. [2 points]
(e) Suppose every chosen address in Method 1 responds. To what group can the agency generalize its results? Justify your answer. [1 point]

The question

A survey about a new bus route