Does burning areas of an ecosystem improve the performance of native grasses? A team of ecologists tested this on 50 fields. Assume the researchers performed an experiment and calculated a p-value of 0.024.  Complete the statements below: Using a significance level of 0.05, the researchers should the null hypothesis. It is possible that they have committed a type error.

In a survey, students are asked how many hours they study in a typical week. A five-number summary of the responses is included.    Min Q1 Med Q3 Max 5 9 14 20 50   Use the information from this five-number summary to identify the quantities listed below.

Assume that SAT-math scores are normally distributed with mean 500 points and standard deviation 100 points. Taylor scored 650 on the SAT-math test.  Taylor’s standardized score (z-score) is ? 95% of the SAT-math scores would lie between

A randomly selected sample of n = 20 activity monitor/ tracker users completed a survey. These activity monitor/ tracker users indicated that they walked on average 8,000 steps per day with a standard deviation of 90 steps per day. The calculated standard error of the mean is 20.1 steps per day. Assume that all conditions are met to use the theoretical t distribution for inference.  Which is correct 98% confidence interval for the average number of steps walked per day by activity monitor/tracker users?

Consider the StatKey output below that provides a bootstrap distribution for the difference in proportions:   Use all provided information. The normal approximation of this bootstrap distribution is: N(

The table below shows the responses from a sample of 680 people in the General Social Survey to the question, “Do you sometimes drink more than you think you should?” The data is separated by sex.   No Yes Total Female 260 92 352 Male 177 151 328 Total 437 243 680 What is the correct calculation of the relative risk for females who said “yes” when compared to males?

A study finds that cars made by one car manufacturer tend to receive a lower safety score than cars made by another car manufacturer in crash tests where a small crash test adult dummy is used in each test.  With this study, a possible confounding variable is:

A new vaccine was recently tested to see if it could prevent the painful and recurrent ear infections that many infants suffer from. The Lancet, a medical journal, reported a study in which babies about a year old were randomly divided into two groups. One group received vaccinations; the other did not. During the following year, only 333 of 2455 vaccinated children had ear infections, compared to 499 of 2452 the unvaccinated children in the control group. The goal is to determine if the vaccine is effective What analysis should be used to answer this question?

The figure below displays four different normal distributions.   Match the lines above to the correct parameters found with each normal distribution Orange (dashes and dots): N(

How has net worth changed over time for different generations? This graph explores this topic from 1989 to 2016 when considering four generations.