A quality improvement team at a clinic randomly selected 11 patients and recorded their wait times after implementing a new check-in system. Before the new check-in system, the mean wait time was 22 minutes, and the standard deviation was 8 minutes.  Here are the measurements for the wait times from the sample:       10,    15,   20,   17,   30,   25,   15,   12,   12,   15,   17 The type of graph being used to display wait times is called a [a]. The shape of the distribution of wait times is [b]. The team conducting the study want to estimate the mean wait time using the new check-in system using these 11 randomly selected wait times.  To do so, they should use a(n) [c].

Some individuals are carriers of the bacterium Streptococcus pyogenes. Investigators examined 1398 schoolchildren to determine if they were carriers or not, and noted the size of their tonsils.  Here are the results: Tonsil Size normal large very large Total Carrier 19 29 24 72 Non-carrier 497 560 269 1326 Total 516 589 293 1398  Which of the following hypotheses should be used to test if the relationship between carrier status and tonsil size is statistically significant?

A brewing company employee was interested how to improve corn yields.  There is reason to suspect that drying the seeds in a kiln before planting them might improve yield.  The employee had access to 9 small plots of land.  Because soil fertility might vary from plot to plot, he divided each plot in half and planted regular seed in one half and kiln-dried seed in the other (randomly deciding which kind of seed was planted in each half plot).  Following are the resulting data (yield is measured in pounds per acre). What experimental design is this? [design] The appropriate hypothesis test was performed on the above data and resulted in a p-value of 0.0704.  Using the 0.05 level of significance, the correct conclusion is [conclusion]. Plot Kiln-dried seed Regular seed Difference in yield 1 2009 1903 106 2 1915 1935 – 20 3 2011 1910 101 4 2463 2496 – 33 5 2122 2060 62 6 1482 1444 38 7 1542 1612 – 70 8 1443 1316 127 9 1535 1511 24  

For an exit poll of a recent ballot issue as to whether a county tax should be imposed to fund public transportation, 53.1% of those polled said ‘yes.’  Which of the following statistical inference procedures should be used to determine if the majority of the population approved of the tax?

A sociologist studying how freshmen at a major university manage their time carried out a survey. The sociologist used the freshman enrolled in an introductory sociology class to carry out the survey. The population of interest is [a]. The sample is [b].

Although universities have no preference between the ACT and SAT tests, as of 2019 55% of students take the SAT test.  An educational researcher wants to know if there are regional differences in the United States between the tests that students takes.  The researcher takes a random sample of 1000 students from high schools in the Midwest and calculates the percentage taking the SAT to be 58.6%. The parameter is [Parameter]. The statistics is [Statistic].

Is the following statement true or false?   If the Fed wishes to decrease the supply of money and credit, it may sell government securities, raise the discount rate, or lower required reserve ratios.

Is the following statement true or false?   If the Fed wishes to decrease the supply of money and credit, it may sell government securities, raise the discount rate, or lower required reserve ratios.

In response to the destructive bank panics of the Great Depression, future bank panics are designed to be prevented by

In response to the destructive bank panics of the Great Depression, future bank panics are designed to be prevented by