5. ANOVA calculations and rejection of the null hypothesis Aa Aa The following t

Question

5. ANOVA calculations and rejection of the null hypothesis Aa Aa The following table summarizes the results of a study on SAT prep courses, comparing SAT scores of students in a private preparation class, a high school preparation class, and no preparation class. Use the information from the table to answer the remaining questions Number of Sum of Observations Sample Mean Squares (SS) 650 645 625 Treatment Private prep class High school prep class No prep class 60 60 60 132,750.00 147,500.00 162,250.00 Using the data provided, complete the partial ANOVA summary table that follows. (Hint: T, the treatment total, can be calculated as the sample mean times the number of observations. G, the grand total, can be calculated from the values of T once you have calculated them.) Sum of Squares (SS) df Source Between treatments Within treatments Mean Square (MS)

Explanation / Answer

(second part) right choice is fourth.The SS total is someties easier to calculate than SSbetween. ..........you can use SStotal to calculate SSbetween

(third part) In ANOVA, the F test statistic is the Ratio of the between-treatments variance and the within-treatments variance. The value of the F test statistic is 4.20.

(fourth part) When the null hypothesis is true, the F test statistic is 3.2. When the null hypothesis is false, the F test most likeiy more than critical value. In general, you should reject the null hypothesis for alternate hypothesis

within SS between SS Group n mean(xj-) n*xj- (n-1)s2 (xj--x-) nj(xj--x-)2 1 60 650 39000 132750 10 6000 2 60 645 38700 147500 5 1500 3 60 625 37500 162250 -15 13500 sum 180 1920 0 115200 442500 0 21000 grand mean(x-) 640 (first part) ANOVA SOURCE DF SS MS F CRITICAL F(0.05) BETWEEN 2 21000 10500 4.20 3.05 WITHIN(ERROR) 177 442500 2500 TOTAL 179

Related Questions

Navigate

• Browse (All)
• Browse 5
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.