AP® Statistics 2006 Scoring Guidelines Form B The College Board: Connecting Students to College Success The College Board is a not-for-profit membership association whose mission is to connect students to college success and opportunity. Founded in 1900, the association is composed of more than 5,000 schools, colleges, universities, and other educational organizations. Each year, the College Board serves seven million students and their parents, 23,000 high schools, and 3,500 colleges through major programs and services in college admissions, guidance, assessment, financial aid, enrollment, and teaching and learning. Among its best-known programs are the SAT®, the PSAT/NMSQT®, and the Advanced Placement Program® (AP®). 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. © 2006 The College Board. All rights reserved. College Board, AP Central, APCD, Advanced Placement Program, AP, AP Vertical Teams, Pre-AP, SAT, and the acorn logo are registered trademarks of the College Board. Admitted Class Evaluation Service, CollegeEd, connect to college success, MyRoad, SAT Professional Development, SAT Readiness Program, and Setting the Cornerstones are trademarks 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 2006 SCORING GUIDELINES (Form B) Question 1 Intent of QuestionThe primary purpose of this question is to assess a student’s ability to read, interpret, and explain information contained in a cumulative relative frequency plot for a real estate company.SolutionPart (a): This point indicates that 40 percent of the sales agents at this real estate company had sales volume of $300,000 or less in the month shown. Part (b): Eighty percent of the sales agents had sales volume of $800,000 or less and 70 percent of the sales agents had sales volume of $700,000 or less. Thus, 0. or 10 percent of the sales agents achieved monthlysales volumes greater than $700,000 and not exceeding $800,000. 80.70.1-=Part (c): There were no agents whose monthly sales volume was between $1,000,000 and $1,100,000. Part (d): The 80th percentile for the distribution of monthly sales volume by these agents during the preceding month is $800,000. Therefore, an agent making more than $800,000 will be in the top 20 percent. ScoringParts (a), (c), and (d) are scored as essentially correct (E), partially correct (P), or incorrect (I). Part (b) is scored as essentially correct (E) or incorrect (I). Part (a) is essentially correct (E) if both values are correctly identified and interpreted in the appropriate context. Part (a) is partially correct (P) if incorrect values are read from the plot, but the interpretation is correct OR one of the values is not interpreted correctly in the context of the question. Part (a) is incorrect (I) if the student fails to recognize the cumulative nature of the graph, for example, the student says 40 percent of the sales agents had a sales volume of $300,000. Part (b) is essentially correct (E) if 0.1 (or 10 percent) is provided AND work is shown or an appropriate explanation is provided. Part (b) is incorrect (I) if an answer (0.1, 0.8, or anything else) is provided with no supporting work or explanation. © 2006 The College Board. All rights reserved. Visit apcentral.collegeboard.com (for AP professionals) and www.collegeboard.com/apstudents (for students and parents).2 www.mymathscloud.com
AP® STATISTICS 2006 SCORING GUIDELINES (Form B) Question 1 (continued) Note: Probability statements are OK and work may be provided on the graph. Alternative solution to Part (b): Let X represent monthly sales volume (in hundreds of thousands of dollars) © 2006 The College Board. All rights reserved. Visit apcentral.collegeboard.com (for AP professionals) and www.collegeboard.com/apstudents (for students and parents).0.1()()()78870.80.7PXPXPX<£=£-£=-=, so 0.1 (or 10 percent) of the sales agents achieved monthly sales volumes greater than $700,000 and not exceeding $800,000. Part (c) is essentially correct (E) if the student indicates that none of the sales agents had a monthly sales volume between $1 million and $1.1 million. Part (c) is partially correct (P) if the student recognizes that no events occurred between 10 and 11 but does not provide a correct description in the context of this problem. Part (c) is incorrect (I) otherwise, for example, if the student says the number of agents with $1 million in sales is the same as the number of agents with $1.1 million in sales, or if the student says that the frequency of sales of $1 million is the same as the frequency of sales of $1.1 million. Part (d) is essentially correct (E) if a minimum monthly sales volume above $800,000 is identified or the student says anything above $800,000 will qualify the agent for a bonus AND justification for selecting that value is provided using the complement rule or the graph. Part (d) is partially correct (P) if the minimum monthly sales volume is specified as $800,000 with no justification. Part (d) is incorrect (I) if an incorrect minimum monthly sales volume is specified OR a value is specified without context. Each essentially correct response is worth 1 point; each partially correct answer is worth ½ point. 4 Complete Response 3 Substantial Response2 Developing Response1 Minimal Response If a response is between two scores (for example, 2½ points), use a holistic approach to determine whether to score up or down depending on the strength of the response and communication. 3 www.mymathscloud.com
