1. MATHEMATICS & COMPUTER SCIENCE DVC 2015-16

2. WELCOME STATISTICIANS!  Sit in your project seat  Take out a page to write down notes

3. AGENDA I. Survey strengths and weaknesses II. Appendix structure III. Research Paper and Business Plan data incorporation

5. MARGIN OF ERROR What is “ERROR” when talking about survey results? What factors introduce error into survey results?

6. SMALL SAMPLE

7. NON-RANDOM SAMPLE What factors affected who you spoke with on the streets of L.A.? Selection Bias  Individuals can be unwilling to participate so we don’t hear their opinion; these individuals could be very different from those who voluntarily share their opinion. Response Bias  Most people like to present themselves in a favorable light so they might not answer uncomfortable questions honestly. If respondents are surveyed together, one person’s response could influence another person’s response.

8. UNREPRESENTATIVE SAMPLE REPRESENTATIVE SAMPLEOUR SAMPLE White  400 * 0.268 = 107.2107 Black  400 * 0.092 = 36.874 Latino  400 * 0.484 = 193.6103 Asian  400 * 0.148 = 59.249 American Indian  400 * 0.015 = 60 Pacific Islander  400 * 0.004 = 1.610 Two or More Races  400 * 0.029 = 11.628

9. PEW METHODOLOGY Large samples. Representative samples. Random samples.

12. APPENDIX A

13. PACK UP: Log off Monitor on Sit in your seat