BUSINESS STATISTICS 4-1 Sampling and Sampling Distribution
4 Sampling and Sampling Distributions
Using Statistics
Sample Statistics as Estimators of
Population Parameters
Sampling Distributions
Estimators and Their Properties
Degrees of Freedom
Summary and Review of Terms
ernational University – School of Business Assoc. Prof. Ho Thanh Phong
, BUSINESS STATISTICS 4-2 Sampling and Sampling Distribution
4.1. Statistics is a Science of Inference
• Statistical Inference: On basis of sample statistics
– Predict and forecast values of
population parameters... derived from limited and
– Test hypotheses about values incomplete sample
of population parameters... information
– Make decisions...
Make On the basis of
generalizations about observations of a
the characteristics of sample, a part of a
a population... population
ernational University – School of Business Assoc. Prof. Ho Thanh Phong
, BUSINESS STATISTICS 4-3 Sampling and Sampling Distribution
4-2 Sample Statistics as Estimators of
Population Parameters
A sample statistic is a A population parameter is
numerical measure of a a numerical measure of a
summary characteristic of summary characteristic of
a sample. a population.
• An estimator of a population parameter is a sample statistic
used to estimate or predict the population parameter.
• An estimate of a parameter is a particular numerical value
of a sample statistic obtained through sampling.
• A point estimate is a single value used as an estimate of a
population parameter.
ernational University – School of Business Assoc. Prof. Ho Thanh Phong
, BUSINESS STATISTICS 4-4 Sampling and Sampling Distribution
4.2.1. Estimators
• The sample mean, X , is the most common
estimator of the population mean,
• The sample variance, s2, is the most common
estimator of the population variance, 2.
• The sample standard deviation, s, is the most
common estimator of the population standard
deviation, .
• The sample proportion, p̂ , is the most common
estimator of the population proportion, p.
ernational University – School of Business Assoc. Prof. Ho Thanh Phong
4 Sampling and Sampling Distributions
Using Statistics
Sample Statistics as Estimators of
Population Parameters
Sampling Distributions
Estimators and Their Properties
Degrees of Freedom
Summary and Review of Terms
ernational University – School of Business Assoc. Prof. Ho Thanh Phong
, BUSINESS STATISTICS 4-2 Sampling and Sampling Distribution
4.1. Statistics is a Science of Inference
• Statistical Inference: On basis of sample statistics
– Predict and forecast values of
population parameters... derived from limited and
– Test hypotheses about values incomplete sample
of population parameters... information
– Make decisions...
Make On the basis of
generalizations about observations of a
the characteristics of sample, a part of a
a population... population
ernational University – School of Business Assoc. Prof. Ho Thanh Phong
, BUSINESS STATISTICS 4-3 Sampling and Sampling Distribution
4-2 Sample Statistics as Estimators of
Population Parameters
A sample statistic is a A population parameter is
numerical measure of a a numerical measure of a
summary characteristic of summary characteristic of
a sample. a population.
• An estimator of a population parameter is a sample statistic
used to estimate or predict the population parameter.
• An estimate of a parameter is a particular numerical value
of a sample statistic obtained through sampling.
• A point estimate is a single value used as an estimate of a
population parameter.
ernational University – School of Business Assoc. Prof. Ho Thanh Phong
, BUSINESS STATISTICS 4-4 Sampling and Sampling Distribution
4.2.1. Estimators
• The sample mean, X , is the most common
estimator of the population mean,
• The sample variance, s2, is the most common
estimator of the population variance, 2.
• The sample standard deviation, s, is the most
common estimator of the population standard
deviation, .
• The sample proportion, p̂ , is the most common
estimator of the population proportion, p.
ernational University – School of Business Assoc. Prof. Ho Thanh Phong
