## Basic Definitions and Concepts

Read section 1 from chapter 1 to further enhance your understanding of the elements of descriptive and inferential statistics. This section will introduce some of the key concepts in statistics and has numerous exercise and examples. Complete the odd-numbered exercises before checking the answers.

### ANSWERS

- A population is the total collection of objects that are of interest in a statistical study.

- A sample, being a subset, is typically smaller than the population. In a statistical study, all elements of a sample are available for observation, which is not typically the case for a population.

- A parameter is a value describing a characteristic of a population. In a statistical study the value of a parameter is typically unknown.

- All currently registered students at a particular college form a population. Two population characteristics of interest could be the average GPA and the proportion of students over 23 years.

- Population.

Sample.

Population.

Sample.

Sample.

- Qualitative.

Qualitative.

Quantitative.

Quantitative.

Qualitative.

- All newborn babies in South America in the last five years.

The average birth weight of all newborn babies in South America in the last five years.

No, not exactly, but we know the approximate value of the average.

- All adults in the region.

The proportion of the adults in the region who have never married.

The proportion computed from the sample, 0.1.

No, not exactly, but we know the approximate value of the proportion.