1. Assume the data below are independent samples from normally distributed populations with the same variance. A B C D 19 11 24 14 21 14 19 16 26 21 21 14 24 13 26 13 18 16 20 17 18 13 Use oneway ANOVA to test for a difference in population means. State the calculated value of F to two places of decimal. 2. For the situation in question 1, state the critical value of F, at the 5% level of significance, to two places of decimal. 3. Lancet (Mar. 29, 1975) reported on the relationship, in children with elevated levels of lead, between age and a measure of wrist flexor and extensor muscle function. The measure involved the number of taps with a stylus on a single metal plate during a 10 second period. The data are x = age in months and y = taps/10 sec. x 73 84 98 112 116 132 150 160 164 180 y 35 40 50 42 46 41 52 52 51 66 Check that you have entered the data correctly. Use the linear regression capacity of your calculator to find the least squares line for this data. State the slope of the line to three places of decimal. 4. Same data as question 3, state the y intercept of the least squares line rounded to one place of decimal. 5. Same data as question 3, state the first residual rounded to three places of decimal. Note that the first residual is the residual of the first data value as the data is presented above, not the residual of the smallest data value. 6. Same data as question 3. State the value of se rounded to 3 places of decimal. 7. Same data as question 3. State the lower boundary of the 95% prediction interval for the value of y for a particular child with elevated lead levels, Anova Doe, who is 10 YEARS old. State your answer rounded to one place of decimal. Note that this is a twotailed interval, but you are entering only the lower boundary as your answer. You are asked for the lower boundary only in this question and the next because Moodle wants ONE answer only and cannot handle both ends of an interval. If you were 95% confident that y falls, say, between 12.2 and 18.6, then thelower boundary of your interval would be 12.2. [Many people have had difficulty finding the y0hat value needed for this solution. Once you have the (x,y) data entered in your calculator, you input the x0 value in the example on pages 138 and 139 in the course notes this was 104, which was 2 years converted to weeks and then your calculator will find the y 0hat value when you press shift and 2, scroll past the [A B r] screen to the [x 0hat y0hat] screen and press 2 for y0hat and =. What your calculator is doing is simply substituting the x0 value that you give it into the yhat equation.] 8. Same data as question 3. State the lower boundary of the 95% confidence interval for the mean value of y for all children with elevated lead levels who are 10 YEARS old. State your answer rounded to one place of decimal. Note that this is a twotailed confidence interval, but you are entering only the lower boundary as your answer. 9. Analysis of variance is a method by which we decide whether or not observed differences among more than two sample variances can be attributed to chance. Select one: True False 10. It is valid to use the yhat line to make estimations and predictions without further analysis as long as we reject the null hypothesis of no linear relationship between X and Y. Select one: True False