Chapter 12: Statistics - Sampling, Frequency Distributions, and Graphs

Flashcards covering key vocabulary terms related to sampling, frequency distributions, and graphs from Chapter 12: Statistics Section 12.1.

Statistics

The science of collecting, organizing, and summarizing data (descriptive statistics) so that valid conclusions can be drawn from them (inferential statistics).

Population

The set containing all the people or objects whose properties are going to be described and analyzed by the collector.

Census

A count or measure of an entire population.

Sample

A count or measure of part of a population.

Biased Sample

A sample that is not representative of the population from which it is drawn.

Random Sample

A sample obtained in such a way that every element in the population has an equal chance of being selected for the sample.

Representative Sample

A sample that should exhibit characteristics typical of those possessed by the target population.

Random Sampling (Method)

A sampling method where each element in the population is identified, assigned a number, and random numbers are generated to select the sample elements.

Stratified Sampling

A sampling method where members of the population are divided into two or more subsets (strata) that share a similar characteristic, and a sample is then randomly selected from each strata.

Cluster Sampling

A sampling method where the population is divided into groups (clusters), and all members of one or more (but not all) of the clusters are selected.

Systematic Sampling

A sampling method where members of the population are ordered, a starting number is randomly selected, and then sample members are selected at regular intervals from the starting number.

Frequency Distribution

A way to present collected data, consisting of two columns with data values listed in one and the frequency of data values in the other.

Grouped Frequency Distribution

A method of organizing data by creating groups or classes of data to make results more meaningful.

Lower-class Limit

The leftmost number in each class or group of a grouped frequency distribution.

Upper-class Limit

The rightmost number in each class or group of a grouped frequency distribution.

Class Width

The difference between two consecutive lower-class limits (or upper-class limits) in a grouped frequency distribution.

Class Boundaries

The numbers that separate classes in a grouped frequency distribution without forming gaps between them.

Histogram

A bar graph with bars that touch, where the x-axis typically represents class boundaries and the y-axis represents frequency or relative frequency.

Frequency Polygon

A graph created by placing a point on the top center (midpoint) of each rectangle in a histogram and then drawing a straight line connecting these points.