Question

In: Statistics and Probability

A study explored the effect of ethanol on sleep time. Fifteen rats were randomized to one...

A study explored the effect of ethanol on sleep time. Fifteen rats were randomized to one of three treatments. Treatment 1 was water (control). Treatment 2 was 1g of ethanol per kg of body weight, and Treatment 3 was 2g/kg. The amount of REM sleep (in minutes) in a 24hr period was recorded:

Treatment 1 63 54 69 50 72
Treatment 2 45 60 40 56
Treatment 3 31 40 45 25 23 28

Are these data strong evidence REM sleep time differs across the three treatment populations?

(a) Graph the data. Why did you choose the graph that you did and what does it tell you?

(b) Create an ANOVA table for the data using your calculator (to prepare for exams). Show your work. You may use R to check your answers.

(c) Evaluate the ANOVA assumptions graphically. Was ANOVA appropriate here?

(d) Based on the ANOVA table, make a conclusion in the context of the problem.

(e) Use R to create 95% CIs for all pairwise comparisons of means using the Tukey-Kramer method. Summarize your results using letter codes. What do you conclude?

Solutions

Expert Solution


Related Solutions

A study explored the effect of ethanol on sleep time. Fifteen rats were randomized to one...
A study explored the effect of ethanol on sleep time. Fifteen rats were randomized to one of three treatments. Treatment 1 was water (control). Treatment 2 was 1g of ethanol per kg of body weight, and Treatment 3 was 2g/kg. The amount of REM sleep (in minutes) in a 24hr period was recorded: Treatment 1: 63, 54, 69, 50, 72 Treatment 2: 45, 60, 40, 56 Treatment 3: 31, 40, 45, 25, 23, 28 Are these data strong evidence REM...
A study explored the effect of ethanol on sleep time. Fifteen rats were randomized to one...
A study explored the effect of ethanol on sleep time. Fifteen rats were randomized to one of three treatments. Treatment 1 was water (control). Treatment 2 was 1g of ethanol per kg of body weight, and Treatment 3 was 2g/kg. The amount of REM sleep (in minutes) in a 24hr period was recorded: Treatment 1: 63, 54, 69, 50, 72 Treatment 2: 45, 60, 40, 56 Treatment 3: 31, 40, 45, 25, 23, 28 Are these data strong evidence REM...
A study was conducted to explore the effects of ethanol on sleep time. Fifteen rats were...
A study was conducted to explore the effects of ethanol on sleep time. Fifteen rats were randomized to one of three treatments. Treatment 1 got only water (control). Treatment 2 got 1g of ethanol per kg of body weight, and treatment 3 got 2g/kg of ethanol. The amount of REM sleep in a 24hr period was recorded, in minutes. Data are below: Treatment 1: 63, 54, 69, 50, 72 Treatment 2: 45, 60, 40, 56 Treatment 3: 31, 40, 45,...
A study was conducted to explore the effects of ethanol on sleep time. Fifteen rats were...
A study was conducted to explore the effects of ethanol on sleep time. Fifteen rats were randomized to one of three treatments. Treatment 1 got only water (control). Treatment 2 got 1g of ethanol per kg of body weight, and treatment 3 got 2g ethanol per kg of body weight. The amount of REM sleep in a 24hr period was recorded, in minutes. Data are below: Treatment 1: 63, 54, 69, 50, 72 Treatment 2: 45, 60, 40, 56 Treatment...
In a biomedical study with rats, a dose-response investigation is used to determine the effect of the dose of a toxicant on their survival time.
In a biomedical study with rats, a dose-response investigation is used to determine the effect of the dose of a toxicant on their survival time. The toxicant is one that is frequently discharged into the atmosphere from jet fuel. For a certain dose of the toxicant, the study determines that the survival time, in weeks, has a gamma distribution with α = 5 and β = 10. What is the probability that a rat survives no longer than 60 weeks?
In a study of smoking and its effects on sleep patterns, one variable is the time...
In a study of smoking and its effects on sleep patterns, one variable is the time that it takes to fall asleep. A random sample of size 12 is drawn from the population of smokers; an independent sample of size 15 is drawn from the population of non-smokers. The mean time to sleep for smokers is 43.70 minutes; for non-smokers it is 30.32 minutes. The sample variance for the time to sleep for smokers is 286.549 min2  while for non-smokers it...
In a study of memory process, rats were first presented with a fear-inducing stimulus on a...
In a study of memory process, rats were first presented with a fear-inducing stimulus on a learning task as soon as they stepped across a line in a test chamber. Afterwards, the rats were divided and given electrical stimulation either 50 or 150 milliseconds after crossing the line. In addition, the rats differed in terms of the area in which the stimulation electrodes were implanted in their brains (Neutral Area, Area A, or Area B). Researchers were interested in the...
In a study of memory process, rats were first presented with a fear-inducing stimulus on a...
In a study of memory process, rats were first presented with a fear-inducing stimulus on a learning task as soon as they stepped across a line in a test chamber. Afterwards, the rats were divided and given electrical stimulation either 50 or 150 milliseconds after crossing the line. In addition, the rats differed in terms of the area in which the stimulation electrodes were implanted in their brains (Neutral Area, Area A, or Area B). Researchers were interested in the...
In a study of memory process, rats were first presented with a fear-inducing stimulus on a...
In a study of memory process, rats were first presented with a fear-inducing stimulus on a learning task as soon as they stepped across a line in a test chamber. Afterwards, the rats were divided and given electrical stimulation either 50 or 150 milliseconds after crossing the line. In addition, the rats differed in terms of the area in which the stimulation electrodes were implanted in their brains (Neutral Area, Area A, or Area B). Researchers were interested in the...
1. Students were provided a one-time survey with questions about course load and sleep habits: -...
1. Students were provided a one-time survey with questions about course load and sleep habits: - Are you taking another course at the same time as biostats? - On a normal night during the summer, how much do you sleep? question: Are sleep times of college students different depending on their course load? a. Cross-sectional and observational b. Cross-sectional and experimental c.Longitudinal (retrospective) and experimental d.Longitudinal (prospective) and experimental e.Longitudinal (prospective) and observational f.Longitudinal (retrospective) and observational 2. An investigator...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT