Statistical Methods

3.6.Interval estimators - case 1

Unit 3 - Estimation

3.6.Interval Estimators
3.6.1.Case 1 - (1- α ) % Interval estimates for population mean when σ is known is given by.

Note:
If σ is unknown then, it is to be replaced by sample standard deviation ,‘s’.

The maximum error (E )given by,



Note:
Larger the sample size( n), lower is the error(E).

The sample size can be determined for the known confidence level by using the formula :