--%>

how you would use randomization in arranging experiment

The design of instrument controls affects how easily people can use them. An investigator used 25 students who were right-handed to determine whether right-handed subjects preferred right-handed threaded knobs. He had two machines that differed only in that one had a knob that turned in a clockwise fashion (right-handed threads), and the other had a knob that turned in a counterclockwise fashion, (left-handed threads). Turning the knobs moved an indicator bar on a scale. The investigator timed how many seconds it took each subject to move the bar a set distance, using each of the two machines, but only their right hand. So, each of the 25 subjects used only their right hand on the two machines, turning one knob clockwise and the other counterclockwise.

a)     Explain briefly how you would use randomization in arranging this experiment 

b)    Do an analysis to determine if the data shows that right-handed people are FASTER, or need LESS time, to operate knobs with right-handed threads that turn in a clockwise fashion compared to knobs that turn in a counterclockwise fashion.  

c)     Construct a 95% confidence interval for the mean time advantage of clockwise over counterclockwise threads for this group of subjects. 

d)    Are clockwise threaded knobs more efficient for right-handed people? What is the ratio, expressed as a percent, of the mean time for using clockwise threads compared to the mean time for using counterclockwise threads? 

   Related Questions in Advanced Statistics

  • Q : Discrete and continuous data

    Distinguish between discrete and continuous data in brief.

  • Q : Pearsons correlation coefficient The

    The table below illustrates the relationship between two variable X and Y. A

  • Q : Describe how random sampling serves

    Explain sampling bias and describe how random sampling serves to avoid bias in the process of data collection.    

  • Q : Problem on Poisson distribution The

    The number of trucks coming to a certain warehouse each day follows the Poisson distribution with λ= 8. The warehouse can handle a maximum of 12 trucks a day. What is the probability that on a given day one or more trucks have to be sent away? Round the answer

  • Q : Probability on expected number of days

    It doesn't rain often in Tucson. Yet, when it does, I want to be prepared. I have 2 umbrellas at home and 1 umbrella in my office. Before I leave my house, I check if it is raining. If it is, I take one of the umbrellas with me to work, where I would leave it. When I

  • Q : Probability of Rolling die problem A

    A fair die is rolled (independently) 12 times. (a) Let X denote the total number of 1’s in 12 rolls. Find the expected value and variance of X. (b) Determine the probability of obtaining e

  • Q : Analyse the statistics of the data

    Assigment Question Select any two manufacturing companies and formulate the cost and revenue functions of the companies. analyse the statistics of the data and then sketch the functions and determine their breakeven points. (Note: You are required to interview the production and sales manag

  • Q : Conclusion using p-value and critical

    A sample of 9 days over the past six months showed that a clinic treated the following numbers of patients: 24, 26, 21, 17, 16, 23, 27, 18, and 25. If the number of patients seen per day is normally distributed, would an analysis of these sample data provide evid

  • Q : Binomial distribution 1) A Discrete

    1) A Discrete random variable can be described as Binomial distribution if is satisfies four conditions, Briefly discuss each of these conditions2) A student does not study for a multiple choice examination and decides to guess the correct answers, If the

  • Q : What is your statistical decision

    Question 1 Do parents with more children travel more than parents of small families? To find out, a survey was done of a large number of adults. Respondents were asked how many children they had and how many times