Many large surveys use a combination of sampling methods, ...

[Marty]

Many large surveys use a combination of sampling methods, applying them one at a time. This is called a (an) __________ sampling plan.
 Fill in the blank(s) with correct word

Question 2

Which of the following situations could cause bias in the results of a telephone survey?
 a. A phone number in the sample was found to be not in service' or disconnected'.
  b. The person who answered the phone refused to participate.
  c. There was no answer, so the interviewer gave up and called someone else.
  d. Each of the above would cause bias in the results.

[carolinefletcherr]

Answer to Question 1

MULTISTAGE

Answer to Question 2

D

[Marty]

TYSM

[kishoreddi]

Gracias!