Population - large collection fo objects persons, places or things
Examples:
All the residents of the Philippines is considered a population.
All the fish in a lake is considered a population.

Samples - small portion or part of a population; also a subgroup, subset, or representative of a population.
Examples:
10,000 Filipinos is a sample of the Philippine population.
175 fish in a lake is a sample of the fish population in the lake.

Parameter - any numerical or nominal characteristic of a population
Examples:
The age of the selected Filipinos (or even of the whole population) is a parameter.
The length of the fish is a parameter.

Statistic - an estimate of a parameter; any value or measurement obtained from a sample
Example:
The average height of the Filipinos is a statistic.
The number of fish with length from 1-2 ft is also a statistic.

Data (singular: datum) - facts, or a set of information or observations under study; may be qualitative or quantitative
Examples:
The age of every Filipino is data.
The length of each fish is data.

a. Qualitative data - can assume values that manifest the concept of attributes; categorical data; cannot be subjected to meaningful artihmetic; cannot be added, subtracted, or divided
Examples:
The gender of Filipinos.
The color of fish.

b. Quantitative data - numerical in nature; obtained from counting or measuring; meaningful arithmetic operations can be dne with this type of data
Examples:
The height of Filipinos.
The weight of fish.

Variable - characteristic or property of a population or smaple which makes the members different from each other; may be classified on the basis of whether they are discrete or continuous and whether they are dependent or independent

a. Discrete Variable - can assume a finite number of values; can assume specific values only; obtained through the process of counting
Examples:
The number of children in a family can only be whole numbers such as 2, 3, 6, etc… but not 2.5 or 3.6.
The number of fins on a fish can only be 1, 2, 3 or 4, etc.

b.Continuous Variable - can assume infinite values within a specified interval; obtained through measuring
Examples:
The height of Filipinos is a continuous variable because it can be 5’6”, 6’1½“, etc.
The weight of fish is also a continuous variable.

c. Dependent Variable - affected or influenced by another variable

d. Independent Variable - affects or influences the dependent variable

Examples:
The grades of Filipino students is influenced by their attendance. The grades are dependent variables, while their attendance is independent.
The number of fish may be affected by the amount of plants in the lake. The number of fish is dependent while the number of plants is independent.

Constant - property or characteristic of a population or sample which makes the members of the group similar to each other
Examples:
The nationality of Filipinos is a constant.
All the bangus fish in a lake is the same species.

This entry was posted on Saturday, January 21st, 2006 at 6:23 am and is filed under 1: Introduction to Statistics. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.