Researchers studied the behavior of birds that were searching for seeds and insects in an Oregon forest. In this forest, 54% of the trees were Douglas firs, 40% were ponderosa pines, and 6% were other types of trees. At a randomly selected time during the day, the researchers observed 156 red-breasted nuthatches: 70 were in Douglas firs, 79 in ponderosa pines, and 7 in other types of trees. Do these data provide convincing evidence that nuthatches prefer particular types of trees when they’re searching for seeds and insects?

The operations manager of a company that manufactures tires wants to determine whether there are any differences in the quality of workmanship among the three daily shifts. She randomly selects 499 tires and carefully inspects them. Each tire is either classified as perfect, satisfactory, or defective, and the shift that produced it is also recorded. The two categorical variables of interest are: shift and condition of the tire produced. The data can be summarized by the accompanying two-way table.   Perfect Satisfactory Defective Total Shift 1 106 124 2 232 Shift 2 66 85 3 154 Shift 3 36 74 3 113 Total 208 283 8 499 A) This sample has degree of freedom:��= If shift and quality are independent, thenB) With any expected count accurate to 2 decimal places, the expected count in row 1 column 1 is�1,1= C) With any component accurate to 2 decimal places, the component value in row 1 column 1 of the table iscomponent1,1= D) �2 value of this sample is�2=  . Round to 2 decimal…

Which scent station showed no significant preference by one insect type over the others? Rotten eggs Manure All scents Dead mouse Rotten peach

The Women’s Institutional Studies group at a Midwestern university wanted to compare the percentages of female faculty members in the various units on campus in Spring 2004.  Of particular interest were the percentages of female faculty in the College of Education and in the College of Business .  In a sample of 80 College of Education faculties, there were 36 females, and in a sample of 70 College of Business faculties, there were 15 females.  Based upon this sample information, which of the following is the 98% confidence interval for the difference in the actual percentages of female faculty between College of Education and College of Business ?   a. (0.075, 0.405).   b. (0.123, 0.357).   c. (-0.012, 0.252).   d. (0.058, 0.422).   e. (0.101, 0.379).