Read the following research description and answer the questions that follow.

Description:

A physician read a newspaper article stating that the incidence of child abuse in this country is on the rise. The article provided estimates of the percentage of children who were abused during the past year in the U.S. The physician was quite skeptical that the number of abused children was as high as that reported in the article. She conducted a survey of all the physicians specializing in children's medicine who worked at the five hospitals in her community. She obtained a list of all such physicians, a total of 103. She then made up a short list of questions regarding the physicians' personal experiences with cases of child abuse. A paid research assistant attempted to contact by telephone each of the physicians. By being persistent, the assistant reached 91 physicians by phone and asked each about his or her experiences with child abuse. Every physician who was contacted agreed to answer all the questions. The researcher found that the number of child abuse cases seen by her respondents was considerably fewer than would be expected given the population of her community and the percentage estimates provided in the newspaper article. She concluded that the author of the newspaper article was seriously overestimating the incidence of child abuse.

1		What type of sampling, probability or nonprobability, was used in this study?
2		It seems likely that the results of this survey are biased. What type of bias is apt to be present: response bias or selection bias? Define each of these types of bias and explain your choice.