The table below is an excerpt from a research article titled "Marital Dissolution among Interracial Couples," published in theJournal of Marriage and Family by Dr. Yuanting Zhang and Dr. Jennifer Van Hook. In this study, they use data from the Survey of Income and Program Participation to examine the stability and instability of marriages in the United States, comparing couples that are racially endogamous (same race/ethnicity) and interracial (different race/ethnicity).

	All Couples	Endogamous Couples	Interracial Couples
Marriage Duration in Years	12.500	12.619	10.449
	(6.950)	(7.000)	(5.914)
Region of Residence
Midwest	0.264	0.271	0.159
Northeast	0.184	0.187	0.138
South	0.350	0.353	0.303
West	0.203	0.189	0.401
N	23,139	21,547	1,592

1. What is the difference in average marriage durations between couples who are endogamous and couples who are interracial? What type of sample statistic is this?
2. Calculate the 95% confidence interval for the statistic that you calculated and identified in part (1).

In this question, we are practicing interpreting point estimates and confidence intervals to draw conclusions about the social world. The numbers in parentheses are 95% confidence intervals.

-In a study published last year, Youngmin Yi, Frank Edwards, and Christopher Wildeman found that in the United States, 11.4% (11.2%, 11.6%) of all Native American children and 5.0% (5.0%, 5.0%) of all white children will be placed in foster care at some point in their life. What is the focal relationship? What can you conclude about the focal relationship?

-A team of medical researchers (Heard-Garris et al. 2018) analyzed data from a nationally representative sample of young adults in the U.S. and found that young adults whose mothers had ever been incarcerated where 14% (-29%, 85%) more likely to have used mental health counseling services than young adults who had not experienced maternal incarceration. What is the focal relationship? What can you conclude about the focal relationship?