The above calculations are to determine your Sum of Squares value for the Difference Scores. Use that ending value and the other values needed from the scenario to fill out the form on the next page. Doing this whole worksheet will help tremendously when doing your first exam word problems. @ Symbols Values Notes column ... MDiff SSDIFF Note: this is "always" 0 in a dependent t-Test df n-1 SSown/df; Round to 3 decimals. SDiff Square root of Saw, Round to 3 decimal places SMDiff SoW /N; Round to 2 decimal places. SMDWY Square root of S'MDW: Round to 3 decimal places. Obtained t Moir - How/ SMow, Round final t-score to 2 decimals. Critical t t cutoff using df, a=.05, and two-tailed Decision (reject null or Type answer as "Reject" or "Fail to Reject" fail to reject null) (.whichever of those two is correct). Estimated d value Moir / Sown; Round to 2 decimals. Effect size S, M, or L Type answer as "Small" or "Medium" or "Large" (..whichever of those three is correct). You can use the space below to draw the bell curve to help you "see" whether the difference is significant visually. Values showing on the horizontal line are standard deviation values to help guide you when marking where the "critical region values" start and then where your "obtained t-value" should appear. -3 Remember, you can use your study guide during the exam. There is no need to "memorize" information. This study guide should provide you with the items to focus on during your studying. You will submit a copy of your study guide notes before starting your exam, then all worksheets/tables/etc that are provided for you during class after you have completed the exam. If you get stuck on any of the items above while prepping your notes, please email me. Let me know the part/chapter/item-number, what you think the answer is, or let me know what you "do" understand about it and "where you are getting stuck". I will give feedback or let you know you are on the right track. Page 6Dependent Samples t-Test (a.k.a. Correlated Sample or Repeated Measures) A researcher is trying to help students understand that eating healthier will help with making less errors on their exams. To test this hypothesis, students were asked to chart how many servings of veggies the ate each day for a week prior to the midterm exam. They were then given the midterm exam and number of errors were counted. Since all students ate only about half the recommended daily amount of needed veggies, they were asked to increase their intake of veggies by 5 servings each day for the next two weeks, then they were given an exam very similar to the midterm exam. Again, number of errors were counted. When looking at the "before" and "after" scores for these 10 students, the researchers used an a= .05 significance level, and a two-tailed test to determine, "Did students make significantly less errors when eating more veggies than when they did not eat enough veggies, and if so, how strong was this effect?" (i.e., effect size using the Estimated d proposed by Cohen). Mean Number of errors made when eating low veggies vs eating high veggies Low Veggies High Veggies Diff Diff-Moir (Diff-Moir) 8 4 10 11 9 12 8 10 8 11 14 11 10 12 Moir SSDW The remaining calculations and an area to graph the results are below... Remember, you can use your study guide during the exam. There is no need to "memorize" information. This study guide should provide you with the items to focus on during your studying. You will submit a copy of your study guide notes before starting your exam, then all worksheets/tables/etc that are provided for you during class after you have completed the exam. If you get stuck on any of the items above while prepping your notes, please email me. Let me know the part/chapter/item-number, what you think the answer is, or let me know what you "do" understand about it and "where you are getting stuck". I will give feedback or let you know you are on the right track. @ Page 5