Suppose that, for at-test, your computed value fort is +3.28. The critical value oft is +2.048. Explain what this means. Do you reject the null hypothesis or not? Now suppose that you have 28 degrees of freedom and are using a two-tailed (nondirectional) test. Draw a simple figure to illustrate the relationship between the critical and the computed values oft for this result.
Mentally stimulating work requires middle-aged and older adults to grapple with novel situations. Research suggests that continuously confronting complex, novel tasks contributes importantly to cognitive development, predicting gains in cognitive flexibility and reducing the age-related decline in fluid abilities (Bowen, Noack, & Staudinger, 2011 ). Once again, we are reminded of the plasticity of development. Cognitive flexibility is responsive to work experiences well into middle adulthood and perhaps beyond. Designing jobs to promote intellectual stimulation and challenge may be a powerful means of fostering higher cognitive functioning later in the lifespan.
image27 Adult Learners: Becoming a Student in Midlife
Adults are returning to undergraduate and graduate study in record numbers. During the past three decades, students age 25 and older in U.S. colleges and universities increased from 27 to 39 percent of total enrollment, with an especially sharp rise in those over age 35 (U.S. Department of Education, 2012 ). Life transitions often trigger a return to formal education, as with Devin and Trisha’s friend Anya, who entered a nursing program after her last child left home. Early marriage (which often disrupts women’s educational pathways), divorce, widowhood, a job layoff, a family move, a youngest child reaching school age, older children entering college, and rapid changes in the job market are other events that commonly precede reentry (Hostetler, Sweet, & Moen, 2007 ; Moen & Roehling, 2005 ). Among a sample of African-American women, additional motivations included serving as a role model for children and enriching their ethnic community as a whole (Coker, 2003 ).