Medical errors are common in hospitals throughout the world. One possible causal factor is the long work hours of hospital personnel. In a pilot study investigating this issue, medical residents were encouraged to sleep 6-8 hours per night for a 3-week period instead of their usual irregular sleep schedule. The researchers expected, given previous data, that there would be one medical error per resident per day on their usual irregular sleep schedule.
Suppose two residents participate in the program (each for 3 weeks), and chart review finds a total of 20 medical errors made by the two residents combined.
What test can be used to test the hypothesis that an increase in amount of sleep will change the number of medical errors per day?
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EBK FUNDAMENTALS OF BIOSTATISTICS
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- Video Games. A pathological video game user (PVGU) is a video game user that averages 31 or more hours a week of gameplay. According to the article “Pathological Video Game Use among Youths: A Two-Year Longitudinal Study” (Pediatrics, Vol. 127, No. 2, pp. 319–329) by D. Gentile et al., in 2011, about 9% of children in grades 3–8 were PVGUs. Suppose that, today, seven youths in grades 3–8 are randomly selected. a. Assuming that the percentage of PVGUs in grades 3–8 is the same today as it was in 2011, determine the probability distribution for the number, X, who are PVGUs. b. Determine and interpret the mean of X. c. If, in fact, exactly three of the seven youths selected are PVGUs, would you be inclined to conclude that the percentage of PVGUs in grades 3–8 has increased from the 2011 percentage? Explain your reasoning. Hint: First consider the probability P(X ≥ 3). d. If, in fact, exactly two of the seven youths selected are PVGUs, would you be inclined to conclude that the percentage…arrow_forwardStudy 2: Pill Appearance and Perceived Pain. Does the shape or color of a pain pill influence its effectiveness? Although logically it shouldn’t, whether we believe a drug will work does have a powerful effect on our perceptions (e.g., placebo effect). In this experiment, 4 groups of adult patients were given the same amount of Advil after dental surgery for pain relief, but the color and shape of the pill varied. Researchers hypothesized that an unusual shape or color would lead people to believe the pills were new and special and thus would expect them to be more effective than common round, white pills. Researchers also wanted to know if there is an interaction between shape and color Data Labels ShapePill {1=Round; 2=Diamond} ColorPill {1=White; 2=BlueGreen} Gender {0=Woman; 1=Man; 2=Nonbinary person) Descriptions of the Variables and Descriptive Statistics: Referring to the JASP output, and using sentences, present the descriptive statistics of each group: for example:…arrow_forwardIt appears that there is some truth to the old adage “That which doesn’t kill us makes us stronger.” Seery, Holman, and Silver (2010) found that individuals with some history of adversity report better mental health and higher well-being compared to people with little or no history of adversity. In an attempt to examine this phenomenon, a researcher surveys a group of college students to determine the negative life events that they experienced in the past 5 years and their current feeling of well-being. For n = 18 participants with 2 or fewer negative experiences, the average well-being score is M = 42 with SS = 398, and for n = 16 participants with 5 to 10 negative experiences the average score is M = 48.6 with SS = 370. a.) Is there a significant difference between the two populations represented by these two samples? Include whether you reject or retain the Null Hypothesis. Use a two-tailed test with α = 0.01 b.) Compute Cohen’s d to measure the size of the effect. c.) Write a…arrow_forward
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