Problem: Please summarize the following text
Adverse impact occurs when a selection procedure results in different selection rates for different group members (i.e., minority group members having lower selection rates than majority group members; Alexander, Barrett, & Doverspike, 1983; Guion, 1998). Courts typically turn to the longstanding four-fifths rule in order to assess if adverse impact against a particular sex, race, or ethnic subgroup is occurring. The four-fifths rule states that the selection rate for the minority group should be no less than four-fifths (i.e., .80) that of the selection rate for the majority group (Equal Opportunity Employment Commission, U.S. Department of Labor, & U.S. Department of Justice, 1978). If a selection tool is found to have adverse impact (and is not found to have criterion-related validity), then the organization using that selection tool is highly susceptible to legal challenges on the basis of discrimination. It is important to note that adverse impact can arise from mean differences between subgroups on the selection instruments. In spite of the relation between adverse impact and subgroup differences, it is possible to have subgroup differences and no adverse impact (e.g., hiring situations where there are high selection rates); however, it is extremely rare to have a situation in which there are no subgroup differences and adverse impact (Newman, Jacobs, & Bartram, 2007; Newman & Lyon, 2009). Need Assignment Help?