According to a document from the Kansas Department of Health and Environment, there were 519,544 cases of COVID-19, aged 0 to 109(!), in that state in 2021. The population was 2.935 million, not that much larger than Idaho's population.  A Kansan of unknown age or other demographic data received a positive result using a rapid test with a sensitivity of 55% and a specificity of 99.5%.  What's the probability of this person being actually infected?

A recent PwC survey of 1,379 CEOs from a wide range of industries representing a mix of company sizes from Asia, Europe, and the Americas indicated that CEOs are firmly convinced that it is harder to gain and retain people's trust in an increasingly digitalized world (pwc.to/2jFLzjF). Fifty-eight percent of CEOs are worried that lack of trust in business would harm their company's growth. Which risks arising from connectivity concern CEOs most? Eighty-seven percent believe that social media could have a negative impact on the level of trust in their industry over the next few years. But they also say new dangers are emerging and old ones are getting worse as new technologies and new uses of existing technologies increase rapidly. CEOs are particularly anxious about breaches in data security and ethics and IT outages and disruptions. A vast majority of CEOs are already taking steps to address these concerns, with larger-sized companies doing more than smaller-sized companies. a.…

Researchers wanted to determine if having a computercomputer in the bedroom is associated with obesity. The researchers administered a questionnaire to 394394 ​twelve-year-old adolescents. After analyzing the​ results, the researchers determined that the body mass index of the adolescents who had a computercomputer in their bedroom was significantly higher than that of the adolescents who did not have a computercomputer in their bedroom. Complete parts​ (a) through​ (e) below.​(a) Why is this an observational​ study? What type of observational study is​ this? Why is this an observational​ study? A.The researchers administered a questionnaire to obtain their data without trying to influence an explanatory variable of the study. B.The researchers observed the behavior of the individuals in the study without trying to influence an explanatory variable of the study. C.The researchers tried to influence the outcome of the study. D.The researchers intentionally changed an explanatory…

The National Academy of Science reported that 33%33% of research in mathematics is published by US authors. The mathematics chairperson of a prestigious university wishes to test the claim that this percentage is no longer 33%33%. He does not indicate whether the percentage has increased or decreased since that time. He surveys a simple random sample of 218218 recent articles published by reputable mathematics research journals and finds that 5858 of these articles have US authors. Does this evidence support the mathematics chairperson’s claim that the percentage is no longer 33%33%? Use a 0.020.02 level of significance.       Step 2 of 3 :  Compute the value of the test statistic. Round your answer to two decimal places.