The negative effects of ambient air pollution on children's lung function has been well established, but less research is available about the impact of indoor air pollution. The authors of an article investigated the relationship between indoor air-pollution metrics and lung function growth among children ages 6-13 years living in four Chinese cities. For each subject in the study, the authors measured an important lung-capacity index known as FEV₁, the forced volume (in ml) of air that is exhaled in 1 second. Higher FEV₁ values are associated with greater lung capacity. Among the children in the study, 516 came from households that used coal for cooking or heating or both. Their FEV₁ mean was 1427 with a standard deviation of 325. (A complex statistical procedure was used to show that burning coal had a clear negative effect on mean FEV, levels.) (a) Calculate and interpret a 95% (two-sided) confidence interval for true average FEV, level in the population of all children from which the sample was selected. (Round your answers to one decimal place.) Interpret the resulting interval. We are 95% confident that this interval does not contain the true population mean. We are 95% confident that the true population mean lies above this interval. We are 95% confident that this interval contains the true population mean. We are 95% confident that the true population mean lies below this interval. Does it appear that the parameter of interest has been accurately estimated? O This interval is quite narrow relative to the scale of the data values themselves, so it could be argued that the mean has not been accurately estimated. This interval is quite wide relative to the scale of the data values themselves, so it could be argued that the mean has not been accurately estimated. This interval is quite narrow relative to the scale of the data values themselves, so it could be argued that the mean has been accurately estimated. This interval is quite wide relative to the scale of the data values themselves, so it could be argued that the mean has been accurately estimated. (b) Suppose the investigators had made a rough guess of 320 for the value of s before collecting data. What sample size would be necessary to obtain an interval width of 40 ml for a confidence level of 95%? (Round your answer up to the nearest whole number.)

Water availability is of prime importance in the life cycle of most reptiles. To determine the rate of evaporative water loss of a certain species of lizard at a particular desert site, 34 such lizards were randomly collected, weighed and placed under the appropriate experimental conditions. After 24 hours, each lizard was removed, weighed, and its total water loss was calculated by subtracting its body weight after treatment from its initial body weight. Previous studies have shown that the relative frequency distribution of water loss for this species of lizard has a mean of 3.1 grams and a s.d. of 0.8 gram. a) What is the approximate sampling distribution of x , the mean water loss of the 34 lizards

The depth of wetting of a soil is the depth to which water content will increase owing to extemal factors. The article "Discussion of Method for Evaluation of Depth of Wetting in Residential Areas" (J. Nelson, K. Chao, and D. Overton, Journal of Geotechnical and Geoenvironmental Engineering, 2011:293-296) discusses the relationship between depth of wetting beneath a structure and the age of the structure. The article presents measurements of depth of wetting, in meters, and the ages, in years, of 21 houses, as shown in the following table. Age Depth 7.6 4 4.6 6.1 9.1 3 4.3 7.3 5.2 10.4 15.5 5.8 10.7 4 5.5 6.1 10.7 10.4 4.6 7.0 6.1 14 16.8 10 9.1 8.8 Compute the least-squares line for predicting depth of wetting (y) from age (x). b. Identify a point with an unusually large x-value. Compute the least-squares line that results from deletion of this point. Identify another point which can be classified as an outlier. Compute the least-squares line that results from deletion of the outlier,…

Hutchinson-Gilford progeria syndrome is a rare genetic condition that produces rapid aging in children. In individuals with this syndrome, cardiovascular disease is a common cause of death in the teenage years. A clinical study examined the effect of treatment with the drug lonafarnib on a number of physiological outcomes. The researchers measured the pulse wave velocity (PWV) of 18 children diagnosed with progeria and recruited worldwide. The study reports that the mean PWV of 18 children diagnosed with progeria is 12.44 m/s, and the standard deviation is 3.638 m/s. Assuming that PWV is normally distributed, is there significant evidence that the mean PWV of children with progeria is abnormally high (i.e. greater than 6.6 m/s)? Let �  (pronounced as "mu") be the true mean PWV of children with progeria.  What are the two competing hypotheses?       ["", "", "", ""]  What is the test statistic?       ["", "", "", ""]  What is the p value?       ["", "", "", ""]  What is the rejection…