Title: Psych 230 Lecture 1 Psychological Measurement & Statistics Fall 2012 MWF 10:00 – 10:50 Aero & Mech Engr S202 .Instructor: Rosemary A Rosser, PhD (rrosser@email.arizona.edu) Office hours: MW 11-12 Psych 101 Teaching assistants: Melissa Soenke and Lauritz Dieckman Course Description This is designed as a first introduction to statistics for students seeking grounding in the quantitative data analysis associated with conducting behavioral research. I have taught similar courses, including more advanced ones at the graduate level, for 30+ years; and, weird as it might seem, I love it. I approach statistics as a tool for furthering the research enterprise. For me, statistics provides a mechanism for buttressing conceptual arguments; so we will be talking lots about the research context as well as focusing on the logic and the math of the endeavor. I have done many kinds of research in those 30 years--from studies of infant cognition, the acquisition of knowledge in science, spatial cognition, to name a few of the topics. My approach to the content could be described as "conceptual", but I need to make clear what that both means and does not mean. First, the course is not designed as a cookbook application approach where you learn to plug a bunch of numbers into a computer, crunch the data, and trust the machine to give you some sort of answer. Data are seldom self-evident, and without a conceptual understanding of the procedures we use--and what we are assuming about the nature of reality when we use them--those data are apt not to be interpretable. You will learn how to crunch data, albeit with small data sets, but more importantly I hope you will learn what the outcome of the crunching tells us about our phenomena. Second, I do not expect students to necessarily fully appreciate all of the formal, elegant mathematics that underlie the procedures we employ, i.e., you won't have to do lots of derivations and formal mathematical proofs. However, some appreciation of that mathematical foundation is precisely what makes our use of the tool meaningful and a good fit with our research problems. Formulas are conceptual statements; that will be part of the presentation. So, you need to be able to follow some of those proofs and appreciate the interconnection and underlying logic of what we do and what we assume when we use these procedures. Basically, then, this course is about the logic and rationale for using statistical procedures in the behavioral sciences and what those procedures yield. You will learn how the procedures work, what the outcome of the application means, including the relevant computation. The main focus will be on quantitative data analysis and specifically on parametric procedures. It is not assumed that students enter the class with lots of mathematical training. Statistics is basically arithmetic, though a good working knowledge of algebra is essential as well. Calculus is very nice but not necessary at this level and with the approach I take…acquaintance with logic and probability helps though. Also, I have found that students without a good grounding in math, at least college algebra, experience considerable difficulty. Check the material in Kirk’s book in Appendix A and test yourself. There is also a good review of important concepts related to each of the test questions. The textbook and reading The book is Kirk, R.E. (2007). Statistics: An Introduction. Belmont, CA. Thomson/Wadsworth. I have used various editions of this book and find it to be very clear and thorough, similar in philosophical perspective to my own and a good resource should you choose to continue with the subject matter. Requirements for the course There will be 4 midterms and a comprehensive final, (25 points for each midterm and 50 points for the final). You may drop one of the midterms but not the final. The midterms and final will be primarily multiple-choice items, some short answer, and some simple computation. We plan to administer the exams on line. There will also be extra credit, on line quizzes for those who wish to improve a midterm score. If you get 80% or more on an extra credit quiz, you will earn 10 points toward your final point total. There are no partial points on the extra credit quizzes. In addition, there will be “pop” quizzes for an opportunity to earn extra credit points. The purpose of these is to reward those who attend class and keep up with the posted notes. Students who do not attend class regularly tend to experience difficulty with this material. Study Guides I will provide study guides for all the exams, which will be posted to the website, to help you master the material. Note also that all my lectures will be posted prior to our discussion of a topic. These are not power points, as I consider them too sketchy; they are complete textual outlines of what I will talk about. The only thing missing in them will be formulas, derivations, diagrams, etc. If you copy the notes and bring them to class, you can easily fill in the additional mathematics. There will also be practice problems posted on the website also; and the solutions will be available too. These exercises will not be graded, but they offer a way for you to check your understanding and progress with the key concepts and to practice with the mathematics. Grading and Policies The midterms are 25 points each (3 x 25 = 75) The comprehensive final is worth 50….for a total of 125 points possible. My grading breakdown: 90% and up is an A 80%-89% is a B 70-79% is a C 60-69% is a D And less than 60% is an E Attendance is not required, but it is recommended. Many students find this to be a difficult course; attendance might make it less so. Also, you won't have the computational fill-ins in the notes if you are not there. And, to reiterate, sometimes I give “pop” quizzes or problems, which you would not be eligible for if you are not there. Some nuts and bolts: I will not do make-up exams so do not miss them, and I don't typically give incompletes unless you are in danger of croaking. Note also that this is cumulative content and thus this isn't a crammable-for kind of course. We also have help in the form of weekly reviews through ThinkTank, which students have found invaluable. We also must address the problem of academic integrity, especially since the exams are on-line. For a fuller discussion of policy, I refer you to the u of a website. But briefly, it is not expected that you collaborate in test taking---studying of course, but do not collaborate on the tests. I do realize that you may consult your notes during an on-line exam. However, given the length of the exams and the nature of the items, it would be very difficult to do well on one of my tests just by checking notes at the time of testing. Studying with the guides I will supply is a better strategy. We will have procedures built into to the tests themselves designed to detect any cheating. Should I find “cheaters” or “collaborators”, I am required by university policy to report such conduct to the Dean of Students. I will introduce you to my “Cheater-eater” later this week. The course schedule The following are the dates that topics will be discussed, when exams take place; and the C notations indicate what chapters in the text are covered. Aug 20: Introduction to the course 22-24 Logic of science (C1) 27-29 Principles of measurement (C2) 31 Frequency distributions and introduction to central tendency Sept. 3 Holiday—no class 5 Central tendency and review 7 Midterm #1 10-12 Variability (C4) 14 Extra credit quiz 17-19 More on variability 21 The normal curve and z-scores (C4 and parts of C9) 24 Z-scores continued 26 Review for midterm 28 Midterm #2 Oct 1-8 Correlation (C5) 10 The beginning of regression (C6) 12 Extra credit quiz 15-17 Regression continued (C6) 19-22 Transition to probability (C7, 8, 9) 24 Review for midterm 26 Midterm #3 29-31 Probability & inference (C10) Nov 2 Extra credit quiz 5-9 More on inference (C11, 12, 13) 12 Holiday—no class 14 Catch up and review 16 Midterm #4 19-21 More inference and catching up 23 Thanksgiving—no class 26 Extra credit quiz 28-Dec 3 Continuation of inference Dec 5 Comprehensive review for the final Day of scheduled final: The final exam