AP® Statistics 2010 Scoring GuidelinesThe College BoardThe College Board is a not-for-profit membership association whose mission is to connect students to college success and opportunity. Founded in 1900, the College Board is composed of more than 5,700 schools, colleges, universities and other educational organizations. Each year, the College Board serves seven million students and their parents, 23,000 high schools, and 3,800 colleges through major programs and services in college readiness, college admission, guidance, assessment, financial aid and enrollment. Among its widely recognized programs are the SAT®, the PSAT/NMSQT®, the Advanced Placement Program® (AP®), SpringBoard® and ACCUPLACER®. The College Board is committed to the principles of excellence and equity, and that commitment is embodied in all of its programs, services, activities and concerns.© 2010 The College Board. College Board, ACCUPLACER, Advanced Placement Program, AP, AP Central, SAT, SpringBoard and the acorn logo are registered trademarks of the College Board. Admitted Class Evaluation Service is a trademark owned by the College Board. PSAT/NMSQT is a registered trademark of the College Board and National Merit Scholarship Corporation. All other products and services may be trademarks of their respective owners. Permission to use copyrighted College Board materials may be requested online at: www.collegeboard.com/inquiry/cbpermit.html. Visit the College Board on the Web: www.collegeboard.com.AP Central is the official online home for the AP Program: apcentral.collegeboard.com.www.mymathscloud.com
AP® STATISTICS 2010 SCORING GUIDELINES © 2010 The College Board. Visit the College Board on the Web: www.collegeboard.com. Question 1 Intent of Question The primary goals of this question were to assess students’ ability to (1) apply terminology related to designing experiments; (2) construct an appropriate plot that could be used to investigate the fit of a linear model; (3) decide, from a graphical display, whether a linear regression model is appropriate for a set of data. SolutionPart (a): i. The treatments are the different concentrations of garlic in the food granules. Specifically, there are five treatments: 0 percent, 2 percent, 10 percent, 25 percent and 50 percent. ii. The experimental units are the birds (starlings), each placed in an individual cage. iii. The response is the number of food granules consumed by the bird. Part (b): i. The following scatterplot results from these data. ii. The curved pattern in this scatterplot reveals that a linear regression model would not be appropriate for modeling the relationship between these variables. ScoringParts (a) and (b) are scored as essentially correct (E), partially correct (P) or incorrect (I). Part (a) is scored as follows: Essentially correct (E) if the student correctly identifies all three subparts—the treatments, the experimental units and the response that will be measured. Partially correct (P) if the student identifies two subparts correctly. Incorrect (I) otherwise. www.mymathscloud.com
