--%>

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 : Probability of signaling Quality

    Quality control: when the output of a production process is stable at an acceptable standard, it is said to be "in control?. Suppose that a production process has been in control for some time and that the proportion of defectives has been 0.5. as a means of monitorin

  • 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 : 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 : Find the cumulative distribution

    You must use the pre-formatted cover sheet when you hand in the assignment. Out full detailed solutions. Sloppy work will naturally receive a lower score. 1. Suppose at each step, a particle moving on sites labelled by integer has three choices: move one site to the right with pro

  • Q : Frequency Distributions Define the term

    Define the term Frequency Distributions?

  • Q : Variation what are the advantages and

    what are the advantages and disadvantages of seasonal variation

  • Q : Problem on consumers marginal utility

    Consider a consumer with probability p of becoming sick.  Let Is be the consumer’s income if he becomes sick, and let Ins be his income if he does not become sick, with Is < Ins. Suppo

  • Q : Probability problem A) What is the

    A) What is the probability of getting the following sequence with a fair die (as in dice):B) What is the probability of getting the same sequence with a die that is biased in the following way: p(1)=p(2)=p(3)=p(4)=15%;

  • 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 : Non-parametric test what is the

    what is the appropriate non-parametric counterpart for the independent sample t test?