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Agus Darmawan. .

ghoes_wan@yahoo.com

Montgomery, D.C,2003. Applied Statistics and Probability for

, ,

per day for undergraduate students is 4 hours, but thevariance of the time is unknown. A random sample of

size n = 16 is taken from all undergraduate students

and the sample variance is 1 hour2. Compute the.

hours.

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per day for undergraduate students is 4 hours, but thevariance of the time is unknown. A random sample of

size n = 16 is taken from all undergraduate students

and the sample variance is 1 hour2. Compute the.

hours.

Introduction

An interval estimate for a population parameter is

e canno e cer a n a e n erva con a ns etrue, unknown population parameterwe only use a

estimate and the interval.

However, the confidence interval is constructed sothat we have hi h confidence that it does contain theunknown population parameter.

CONFIDENCE INTERVAL ON THE MEAN OF ANORMAL DISTRIBUTION, VARIANCE KNOWN

Suppose that X1, X2,, Xn is a random sample from anormal distribution with unknown mean and knownvariance 2

Now Z has a standard normal distribution.

e resu ng con ence n erva or s

on ence oe c en

CONFIDENCE INTERVAL ON THE MEAN OF ANORMAL DISTRIBUTION, VARIANCE KNOWN

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CONFIDENCE INTERVAL ON THE MEAN OF ANORMAL DISTRIBUTION, VARIANCE KNOWN

CONFIDENCE INTERVAL ON THE MEAN OF ANORMAL DISTRIBUTION, VARIANCE KNOWN

One-sided confidence bounds

Exercises: CONFIDENCE INTERVAL ON THE MEAN OF ANORMAL DISTRIBUTION, VARIANCE UNKNOWN Suppose that X1, X2,, Xn is a random sample from a

normal distribution with unknown mean and unknownvariance 2

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CONFIDENCE INTERVAL ON THE VARIANCE ANDSTANDARD DEVIATION OF A NORMAL POPULATION

CONFIDENCE INTERVAL ON THE VARIANCE ANDSTANDARD DEVIATION OF A NORMAL POPULATION

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CONFIDENCE INTERVAL ON THE VARIANCE ANDSTANDARD DEVIATION OF A NORMAL POPULATION

CONFIDENCE INTERVAL ON THE VARIANCE ANDSTANDARD DEVIATION OF A NORMAL POPULATION

A LARGE-SAMPLE CONFIDENCE INTERVAL FOR APOPULATION PROPORTION

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A LARGE-SAMPLE CONFIDENCE INTERVAL FOR APOPULATION PROPORTION

Choice of Sample Size