Question

In: Statistics and Probability

A random sample of n = 100 measurements is selected from a population with unknown mean...

A random sample of n = 100 measurements is selected from a population with unknown mean µ and known standard deviation σ = 10. (a) (1 point) Calculate the width of a 90% confidence interval for µ.
(b) Calculate the width of a 95% confidence interval for µ.
(c) (Calculate the width of a 99% confidence interval for µ.
(d) Based on the above results, what effect does increasing the confidence coefficient have on the width of the confidence interval.

Solutions

Expert Solution


Related Solutions

A random sample of n measurements was selected from a population with unknown mean μ and...
A random sample of n measurements was selected from a population with unknown mean μ and standard deviation σ=35 for each of the situations in parts a through d. Calculate a 95​% confidence interval for muμ for each of these situations. a. n=75​, x overbarx=22 b. n=150​,x overbarxequals=110 c. n=90​, x overbarxequals=18 d. n=90​,x overbarxequals=4.69 e. Is the assumption that the underlying population of measurements is normally distributed necessary to ensure the validity of the confidence intervals in parts a...
A random sample of n measurements was selected from a population with unknown mean μ and...
A random sample of n measurements was selected from a population with unknown mean μ and standard deviation σ = 15 for each of the situations in parts a through d. Calculate a 99% confidence interval for μ for each of these situations. a. n = 75, x̄ = 27 b. n = 150, x̄ = 105 c. n = 125, x̄ = 16 d. n = 125, x̄ = 5.37 e. Is the assumption that the underlying population of...
A random sample of n measurements was selected from a population with unknown mean m and...
A random sample of n measurements was selected from a population with unknown mean m and standard deviation σ=20σ=20 . Calculate a 99% confidence interval for μμ for each of the following situations: a. n=75,x¯¯¯=28 b. n=200,x¯¯¯=102 c. n=100,x¯¯¯=15  d. n=100,x¯¯¯=4.05 a. n=75,x¯=28  b. n=200,x¯=102  c. n=100,x¯=15  d. n=100,x¯=4.05 e. Is the assumption that the underlying population of measurements is normally distributed necessary to ensure the validity of the confidence intervals in parts a–d ? Explain.
A random sample of n measurements was selected from a population with unknown mean mu and...
A random sample of n measurements was selected from a population with unknown mean mu and standard deviation sigma equals 20 for each of the situations in parts a through d. Calculate a 95​% confidence interval for mu for each of these situations. a. n=60​, overbar =29 ​(Round to two decimal places as​ needed.) b. n=250​, xoverbare=113 ​(Round to two decimal places as​ needed.) c. n=90​, xoverbar=18 ​(Round to two decimal places as​ needed.) d. n=90​, xoverbar=4.1 ​(Round to two...
A random sample of n measurements was selected from a population with standard deviation σ=13.6and unknown...
A random sample of n measurements was selected from a population with standard deviation σ=13.6and unknown mean μ. Calculate a 90 % confidence interval for μ for each of the following situations: (a) n=35, x=78.5 (b) n=50, x¯=78.5 (c)n=70, x¯=78.5
A random sample of n =100 is selected from a normal population with mean μ =...
A random sample of n =100 is selected from a normal population with mean μ = 24 and standard deviation σ = 1.25. Find the probability that  is less than 24.3
A random sample of ?n measurements was selected from a population with standard deviation 13.913.9 and...
A random sample of ?n measurements was selected from a population with standard deviation 13.913.9 and unknown mean ?μ. Calculate a 9999 % confidence interval for ?μ for each of the following situations: (a) ?=35, ?⎯⎯⎯=104.9n=35, x¯=104.9 (b) ?=60, ?⎯⎯⎯=104.9n=60, x¯=104.9 (c) ?=85, ?⎯⎯⎯=104.9n=85, x¯=104.9 (d) In general, we can say that for the same confidence level, increasing the sample size  the margin of error (width) of the confidence interval. (Enter: ''DECREASES'', ''DOES NOT CHANGE'' or ''INCREASES'', without the quotes.)
A random sample of ?n measurements was selected from a population with standard deviation ?=14.6 and...
A random sample of ?n measurements was selected from a population with standard deviation ?=14.6 and unknown mean ?. Calculate a 99% confidence interval for ? for each of the following situations: (a) ?=45, ?⎯⎯⎯=76.3 ____ ≤?≤ _______ (b)  ?=65, ?⎯⎯⎯=76.3 ____  ≤?≤ ______ (c)  ?=85, ?⎯⎯⎯=76.3 ______ ≤?≤ _______
A random sample of ?n measurements was selected from a population with standard deviation ?=11.7 and...
A random sample of ?n measurements was selected from a population with standard deviation ?=11.7 and unknown mean ?. Calculate a 95% confidence interval for ? for each of the following situations: (a) ?=60, ?=85 ≤?≤ (b)  ?=75, ?=85 ≤?≤ (c)  ?=100, ?=85 ≤?≤
A random sample of n = 100 scores is selected from a normal population with a...
A random sample of n = 100 scores is selected from a normal population with a mean of μ = 60 and a standard deviation of σ = 20. What is the probability of obtaining a sample mean greater than M = 57?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT