In this problem, assume that the distribution of differences is approximately normal. Note: For degrees of freedom d.f. not in the Student's t table, use the closest d.f. that is smaller. In some situations, this choice of d.f. may increase the P-value by a small amount and therefore produce a slightly more "conservative" answer. The western United States has a number of four-lane interstate highways that cut through long tracts of wilderness. To prevent car accidents with wild animals, the highways are bordered on both sides with 12-foot-high woven wire fences. Although the fences prevent accidents, they also disturb the winter migration pattern of many animals. To compensate for this disturbance, the highways have frequent wilderness underpasses designed for exclusive use by deer, elk, and other animals. In Colorado, there is a large group of deer that spend their summer months in a region on one side of a highway and survive the winter months in a lower region on the other side. To determine if the highway has disturbed deer migration to the winter feeding area, the following data were gathered on a random sample of 10 wilderness districts in the winter feeding area. Row B represents the average January deer count for a 5-year period before the highway was built, and row A represents the average January deer count for a 5-year period after the highway was built. The highway department claims that the January population has not changed. Test this claim against the claim that the January population has dropped. Use a 5% level of significance. Units used in the table are hundreds of deer. (Let d = B - A.) 1 23 4 56 7 9 12.7 5.6 17.4 9.9 20.5 16.2 18.9 11.6 Wilderness District 10 B: Before highway 10.1 7.2 9.1 8.2 10.2 4.1 4.0 7.1 15.2 8.3 12.2 7.3 (a) What is the level of significance? State the null and alternate hypotheses. Will you use a left-tailed, right-tailed, or two-tailed test? Hoi Mg-0; Hqi Mg 0; two-tailed O Ho: Mg- 0; H: Hg > 0; right-tailed O Ho: Hg > 0; H: H- 0; right-tailed O Hg: Mg = 0; H,: M < 0; left-tailed (b) What sampling distribution will you use? What assumptions are you making? O The Student's t. We assume that d has an approximately uniform distribution. O The Student's t. We assume that d has an approximately normal distribution. O The standard normal. We assume that d has an approximately uniform distribution. O The standard normal. We assume that d has an approximately normal distribution. What is the value of the sample test statistic? (Round your answer to three decimal places.) (c) Find (or estimate) the P-value. (Round your answer to four decimal places.) O P-value > 0.250 O 0.125 < P-value < 0.25so 0.050 < P-value < 0.125 O 0.025 < P-value < 0.050 O 0.005 < P-value < 0.025 O 0.0005 < P-value < 0.005 Sketch the sampling distribution and show the area corresponding to the P-value. P-value P-value P-value P-value

An office supply company services copiers and tracks how many machines are serviced and the length of time (in minutes) for a service call. The data below for 11 clients is below.   Sum X = 46   Sum Y= 234  Sum XY = 5797       Sum X2 =1180         Sum Y2 =146608     1) Calculate SSYY, SSXX, SSXY   2) Calculate b0, b1   3) Interpret the estimated slope coefficient.

Another measure of central tendency that is rarely used but is easy to calculate is the midrange. It can be found using the formula below. A consumer testing service obtained the mileages (in miles per gallon) shown in the table to the right in five test runs performed with three types of compact cars. Each car manufacturer wants to advertize that its car performed the best in this test. Which of the car manufacturers of cars A, B, and C would prefer to use the midrange statistic in their ads? Explain your reasoning. Midrange= (Maximum data entry) + (Minimum data entry) 2 A 28 33 The manufacturer of (Type an integer or a decimal.) 28 29 35 Car MPG B 32 30 32 25 32 ... C 30 33 24 33 31 would prefer to use the midrange, since their car's midrange of mpg is the of the three models.

Answer part A and D only!

The data table to the right represents the volumes of a generic soda brand. Complete parts (a) and (b) below. a. Which plot represents a dotplot of the data? O A. O C. 50 60 50 70 80 90 Volumes of soda (oz) 60 70 80 90 Volumes of soda (oz) o o Q Q 520 Q Q 5 www. O B. OD. 50 50 60 70 60 Volumes of soda (oz) 70 80 75 70 65 50 元 5 75 75 85 . 70 65 Volumes of soda (oz) 80 90 70 80 90 Volumes of soda (oz) 65 80 70 Q Q Q Q

For a set of observations, Q1 80 and Q3 = 130. Values greater than and less than are possible outliers.

3. Which box plot has the largest interquartile range?

Suppose a researcher collects data on the air pollution levels, measured in milligrams per cubic meter, for both urban and rural areas in 35 states. The data is plotted with urban air pollution levels on the horizontal axis and rural air pollution levels on the vertical axis. Nevada is an outlier in the ?x‑direction. What must be true about this state? The urban air pollution levels for this state are much higher or lower than the rest of the states in the data set. The rural air pollution levels for this state are much higher or much lower than the rest of the states in the data set. This state is an influential observation. The rural air pollution levels for this state are much higher or lower than other states in the data set that have similar urban air pollution levels. The absolute value of the residual of this state is large.

Consider the women's 100-yd dash (and the subsequent 100-m dash) in the Olympics since records have been kept. Determine the best way to combine all data and depict the data. Choose the correct answer below. O A. A line graph would be the best way to show all of the data over time, but some measurements would have to be converted to display the 100-yd and 100-m on the same graph. OB. A scatterplot would show the relationship between the 100-yd dash and the 100-m dash. O C. A stem and leaf plot would be the best way to show all of the data grouped by race times. O D. A histogram would show all of the data by comparing each year. The units of distance would not matter. Click to select your answer. 2:50 PM P Type here to search 3/10/202 Prt Scn End F10 PgUp Home F7 DII B F5 F6