Question

1. Which of the following is correct?

   	A.	Statistics must be based on a simple random sample.
   	B.	Parameters describe population characteristics.
   	C.	Parameter and statistic are two names for the same thing.
   	D.	The population is a subset of the sample.
   	E.	Parameters describe sample characteristics.

2. A 2008 national sample survey interviewed 1,007 people age 18 and older nationwide by telephone. One question asked was whether "on the whole would you say you are satisfied or dissatisfied with the way the nation is being governed?"

A possible source of nonsampling error in this sample survey is

	A.	some people chosen for the sample refused to answer questions.
	B.	people without telephones could not be in the sample.
	C.	some people never answered the phone in several calls.
	D.	Both (A) and (C).
	E.	All of (A), (B), and (C).

3.

A recent survey of 35,101 randomly selected U.S. adults studied the religious affiliation of Americans. An example of a nonsampling error that could affect the results of this survey is

	A.	some people refused to talk about their religion.
	B.	the sampling frame for the survey left out people with no telephone.
	C.	the survey left out Alaska and Hawaii to reduce expenses.
	D.	Both (B) and (C) but not (A).

4.

Is St. John's wort effective in treating attention-deficit/hyperactivity disorder (ADHD) in children and adolescents? A report in a recent issue of the Journal of the American Medical Association describes a study to answer this question.

A randomized, double-blind, placebo-controlled trial was conducted involving 54 children aged 6 to 17 years. Participants were randomly assigned to receive 300 mg of St. John's wort (27 subjects) or a matched placebo (27 subjects) 3 times daily for 8 weeks.

Results. ADHD rating scale scores were measured. Inattentiveness improved 2.6 points with St. John's wort vs. 3.2 points with the placebo.

The experiment was "double-blind." This means that

	A.	neither the subjects nor the people who worked with them knew whether they were taking St. John's wort or placebo.
	B.	the subjects did not know whether they were taking St. John's wort or placebo.
	C.	the subjects did not know that the treatments were intended to reduce their inattentiveness.
	D.	subjects were not allowed to see ads for St. John's wort.

Answer 1

Please don't hesitate to give a "thumbs up" for the answer in case the answer has helped you

As per forum rules we are allowed to answer 1 question per post, hence answering the first question. You may post other questions separately.

1.

A. False, Statitics can be or may not be based on a simple random sample. It can be based on a population too. So, A is wrong
B. True, Parameters describe the population characteristics - Correct.
C. False. Parameters is summary of population. Statistic is summary for sample
D. False, its the other way around. Sample is a subset of population
E. False, parameters describe population characteristics

Answer: B is correct