STA220H5 Lecture Notes - Confidence Interval, Statistical Parameter, Point Estimation
Get access
Related Documents
Related Questions
Consider the following sample of observations on coating thickness for low-viscosity paint. ("Achieving a Target Value for a Manufacturing Process: A Case Study," J. of Quality Technology, 1992:22-26):
0.83 | 0.88 | 0.88 | 1.04 | 1.09 | 1.12 | 1.29 | 1.31 |
1.48 | 1.49 | 1.59 | 1.62 | 1.65 | 1.71 | 1.76 | 1.83 |
Assume that the distribution of coating thickness is normal (a normal probability plot strongly supports this assumption).
(a) Calculate a point estimate of the mean value of coating thickness, and state which estimator you used.
(b) Calculate a point estimate of the median of the coating thickness distribution, and state which estimator you used.
(c) Calculate a point estimate of the value that separates the largest 10% of all values in the thickness distribution from the remaining 90% and state which estimator you used. [Hint: Express what you are trying to estimate in terms of m and s]
(d) Estimate P(X<1.5), i.e., the proportion of all thickness values less than 1.5 [Hint: if you know the values of and , you could calculate this probability. These values are not available , but they can be estimated.]
(e) What is the estimated standard error of the estimator that you used in part (b)?