CH 1.1: Sampling

Question 1

Define Population

Answer 1

A population is the entire collection of objects or outcomes about which information is sought.

Question 2

Define Sample

Answer 2

A sample is a subset of a population containing the objects or outcomes that are actually observed.

Question 3

Define Simple Random Sample

Answer 3

A simple random sample of a size n is a sample chosen by a method in which each collection of n population items is equally likely to compromise the sample, just as in a lottery.

Question 4

Define Sample of Convenience

Answer 4

A sample of convenience is a sample that is not drawn by a well-defined random method.

Question 5

Define Conceptual Population

Answer 5

A simple random sample that consist of values obtained from a process under identical experimental conditions.

Question 6

Define Tangible Population

Answer 6

A simple random sample that consists of a finite number of physical objects.

Question 7

Define Independent

Answer 7

A sample is independent when knowing the values of some items in the sample does not help predict the values of the others. The probability to predict the next item is low.

Question 8

Define Dependent

Answer 8

A sample is dependent when knowing the values of some items in the sample helps predict the values of the others. The ability to predict the next item drawn is high.

Question 9

When are the items in a sample considered independent?

Answer 9

1. The sample consists of a conceptual population.
2. The method, sampling with replacement, is used to make the population behave infinitely large.
3. When the sample of a finite population consists of 5% or less of its population.

Question 10

Define three different types of sampling Methods?

Answer 10

1. Weighted Sampling: Some items are given a greater chance of being selected than others.
2. Strati Ed Random Sampling: The population is divided up into subpopulations, called strata, and a simple random sample is drawn from each stratum.
3. Cluster Sampling: Items are drawn from the population in groups, or clusters.

Question 11

Define One-Sample Experiment

Answer 11

There is only one population of interest and a single sample is drawn from it.

Question 12

Define Multisample Experiment

Answer 12

There are two or more populations of interest, and a sample is drawn from each population.

Question 13

Define Factorial Experiments

Answer 13

In multi-sample experiments populations are distinguished from one another by the varying of one or more factors.

Question 14

Name the two types of Data

Answer 14

1. Numerical/ Quantitative
2. Categorical/Qualitative