The National Association of Realtors (NAR) reported the results of a July 2019 survey of home buyers. One question pertained to the first step in the home search process. In a random sample of 5,870 buyers of a home during the year, 2,583 revealed that their first step was not to contact a realtor, but to look at an online site (e.g., Zillow, Redfin, Trulia) for properties for sale. Consider a realtor who claims that more than one-third of all US home buyers look online for properties as the first step in the home search process.

a. Do the survey results support the realtor’s claim? Test using α = .05.

b. The NAR mailed the survey questionnaire to a nationwide random sample of 159,750 recent home buyers and received 5,870 responses – a response rate of about 3.5%. How might this possibly bias the results?