The deadly Ebola virus is a threat to both people and gorillas in Central Africa. An outbreak in 2002 and 2003 killed 91 of the 95 gorillas in seven home ranges in the Congo. To study the spread of the virus, measure "distance" by the number of home ranges separating a group of gorillas from the first group infected. Here are data on distance and time in number of days until deaths began in each later group. (Data set may be found here.) Distance 1 3 4 4 4 5 Time 4 21 33 41 43 46 (a) Make a scatterplot. Which is the explanatory variable? What kind of pattern does your plot show? (b) Find the correlation r between distance and time.

In a recent study on American sleep habits, 1300 adults were asked questions about their sleep cycles. The study found that 39 % say they get sleepy on the job and their work suffers at least a few days each month. An additional 21 % said the problems occur a few days each week and 9 % say sleepiness on the job is a daily occurrence. For the remaining respondents, sleepiness was not a problem at all. Summarize the given information by filling out the frequency and relative frequency distribution table.  Sleepy At Work? Frequency Relative Frequency Not at all     A few days each month     A few days each week     Daily

The National Safety Board wants to determine the effect of seat belt use on saving lives. One study showed data on children under the age of 5 who were involved in car accidents in which at least one fatality occurred. Below is the table: X1 Survivors (0) Fatalities (1) Total No belt (0) Adult belt (1) Child seat (2) 1129 509 1638 X2 432 73 505 733 139 872 Total 2294 721 3015 Answer in 2 decimal places. a) Determine the probability that a child will be in a child seat. b) Determine the probability that X1 = 0 given X2 = 0 c) What is the probability of X1 = 1 given X2 = 0?

Part A. Depression affects many people. 25 out of 100 people with untreated depression will lose at least one friendship while not receiving treatment. On the other hand, when people with depression are treated with medication and counseling, only 2 out of 100 will lose at least one friendship during treatment. The absolute risk of losing at least one friendship while being treated with medication and counseling is Answer: 2 / 100 = 0.02 = 2%

The National Hurricane Center provides data that list the number of large (category 3, 4, or 5) hurricanes that have struck the United States, by decade, from 1851-2020. Is there sufficient evidence that the number of large hurricanes have remained constant (per decade)? What are the degrees of freedom? Decade Count Decade Count 1851-1860 6 1941-1950 10 1861-1870 1 1951-1960 8 1871-1880 7 1961-1970 6 1881-1890 5 1971-1980 4 1891-1900 8 1981-1990 5 1901-1910 4 1991-2000 5 1911-1920 7 2001-2010 8 1921-1930 5 2011-2020 10 1931-1940 8     Chi-squared test for given probabilitiesdata:  stormsX-squared = 13.589, df = 16, p-value = 0.6293 A. 107                   B. 17                   C. 13.589                    D. 16

Some commercial airlines recirculate about half the air in the cabin during flights as a way to improve fuel efficiency. Other airlines make a policy of NOT recirculating the air and instead, have fresh air from the atmosphere constantly being inserted into the cabin with the “old” air being pumped out of the plane. A total of 1100 passengers flying from San Francisco to Denver were used for an experiment. After their flight, they were each given a list of symptoms associated with the common cold. They were asked to report if they experienced cold symptoms within 24 hours of the flight landing. Of the 517 passengers who flew on planes that recirculate the air, 108 reported post-flight cold symptoms. Of the 583 passengers who flew on airlines that do not use recirculation in the cabin, 110 reported symptoms. Suppose now that we want to use the recirculation of air data to explore “Goal #2”, which is to resolve a hypothesis test about . a) If we want to resolve this hypothesis…

a report about an isolated community claims there are more newborn females than males although we assume equal frequencies for each. Records indicate 628 boys and 718 girls born in the past month. what are Ho and Ha?

Define effect size     in your own words please

A certain virus affects 0.7% of the population. A test used to detect the virus in a person is positive 87% of the time if the person has the virus (true positive) and 14% of the time if the person does not have the virus (false positive). Fill out the remainder of the following table and use it to answer the two questions below based on a total sample of 100,000 people. Virus No Virus TotalPositive Test Negative Test Total 100,000a) Find the probability that a person has the virus given that they have tested positive. Round your answer to the nearest hundredth of a percent and do not include a percent sign. % b) Find the probability that a person does not have the virus given that they test negative. Round your answer to the nearest hundredth of a percent and do not include a percent sign. %

To determine the average length of hospital stay for patients who were hospitalized with and recovered from Covid-19, a physician randomly surveyed 100 of his patients and determined their average length of hospital stay. Identify the population, parameter, sample, and statistic for the above scenario. Write "NONE" for any information that is missing.