How Many Subjects? is a practical guide to sample size calculations and general principles of cost-effective research. It introduces a simple technique of statistical power analysis which allows researchers to compute approximate sample sizes and power for a wide variety of research designs. Because the same technique is used with only slight modifications for different statistical tests, researchers can easily compare the sample sizes required by different designs and tests to make cost-effective decisions in planning a study. These comparisons, emphasized throughout the book, demonstrate important principles of design, measurement and analysis that are rarely discussed in courses or textbooks.

With increased emphasis on helping readers understand the context in which power calculations are done, this Second Edition of How Many Subjects? by Helena Chmura Kraemer and Christine Blasey introduces a simple technique of statistical power analysis that allows researchers to compute approximate sample sizes and power for a wide range of research designs. Because the same technique is used with only slight modifications for different statistical tests, researchers can then easily compare the sample sizes required by different designs and tests to make cost-effective decisions in planning a study. These comparisons demonstrate important principles of design, measurement, and analysis that are rarely discussed in courses or textbooks, making this book a valuable instructional resource as well as a must-have guide for frequent reference.

Do you want to get all A's and still have time to enjoy college? It's possible, but only by studying smarter, not harder. The College Success Cheat Sheet will show you how by helping you master the art and science of rapid, effective learning. Drawing from his journey of failing multiple classes in a community college to graduating with the President's Award from a private university and through interviews with top students from across the country, Jonathan Davidson shares the methods that great students use in order to stand out in college. Now, with this step-by-step guide, you can put these simple ideas into practice and learn how to: * Cut study time and boost long-term memory with the spacing effect, described by researchers as, "[O]ne of the most remarkable phenomena to emerge from laboratory research on learning." * Use English to conquer math * Review textbook chapters in ten minutes or less * Crush even the hardest timed exams * Commit plagiarism to learn how to write stronger papers * Sleep your way to straight A's * Find work during and after college Four years is too much of your life to spend cramming and stressing over your studies. With this guide to college success, you can earn the grades you want and still have time to make the most of your college years. "The College Success Cheat Sheet is efficient and effective while managing to be enjoyable at the same time. The witty, conversational style draws the reader in, and the techniques are based on solid science. I highly recommend it!" -Leslie R. Martin, PhD, co-author of The Longevity Project "Fun, witty, and full of priceless advice. I wish I'd had this book when I was a freshman." - Rachael Lang, college student