Statistical Decision-Making Process:

1
Statistical Decision-Making Process

• Decision Problem
• Statistical Plan
• Data Description and Summary
• Analysis and Conclusions
• Testing Validity of Results
• If Yes, Solution to Decision Problem
• If No, Revise the Statistical Plan

2
A Statistical Plan Includes

• Identification of a Data Base
• Techniques for Describing the Data
• A Means of Analyzing the Data and
• Measures of Validity (Error) in Working with the
  Data

3
Data Base

• Primary Data
• Data collected by observation, experiment,
  simulation or from surveys

• Secondary Data
• Data published by governmental, industrial or
  individual sources

4
Methods of Obtaining Data

• Observation
• Personal Interview
• Telephone Interview and
• Mail Questionnaires

5
Data Levels

• Nominal, where numbers or symbols are used to
  describe an item or characteristic
• Ordinal, where decision makers rank-order the
  observations
• Interval, where the measurement of the distance
  between two data items is allowed
• Ratio, where the data have a unique or zero point