People who design surveys must consider:                                

  a)     The question(s) they are going to ask

       b)    The method of asking the question(s)                                    

       c)     The type of sample they are going to use

What to Ask

                A biased answer is an answer affected by the wording of the question.

                         Example of a biased question:  Would you rather eat pineapple or melons? Or Do you agree that

                     Elvis was the best musician of the 1960's?

How to Ask

                    Mail-in or electronic questionnaires, personal interviews, and telephone interviews are

                    three methods of asking questions.

Deciding Whom to Ask

                        In a random sample, every person in the population has an equally likely chance of being chosen.

                        In a clustered sample, a specialized group of the population is sampled.  For example, if you wish 

                      to know the most popular trucks, you could ask a sample selected randomly from a group who 

                     sold Ford trucks.                                                                                                     

                      Stratified sample, the population is divided into different groups.  Samples are chosen in the same 

                    proportion as the numbers in each group. For example, suppose a kennel club has 200 Cocker 

                    Spaniels, 150 Poodles, and 100 German Shepherd dogs.  A stratified sample might include 20 

                    dogs selected randomly from Cocker Spaniels, 15 from Poodles, and 10 from German Shepherd         

                    dogs.                                                                                      

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