Frequency Distributions in Statistics

These flashcards cover key vocabulary and concepts related to frequency distributions, graphs, and scales of measurement as outlined in the lecture notes.

Frequency Distribution

An organized tabulation showing the number of individuals located in each category on the scale of measurement.

Grouped Frequency Distribution

A method of combining multiple categories to summarize a data set; however, it loses some individual score information.

Proportions

Measures the fraction of the total group that is associated with each score, also known as relative frequencies.

• Formula: p = \frac{f}{N}\n * Where p is the proportion, f is the frequency of scores in a specific category, and N is the total number of scores in the distribution.\n* When to use: Used to represent the relative frequency of a score or category, allowing for comparison across groups of different sizes. It's fundamental for understanding the part-to-whole relationship in a dataset.\n\n

Percentages

Expresses relative frequency out of 100; can be included as a separate column in a frequency distribution table.

• Formula: \text{Percentage} = p \times 100 or \text{Percentage} = \frac{f}{N} \times 100\n * Where p is the proportion, f is the frequency of scores in a specific category, and N is the total number of scores.\n* When to use: Utilized to provide an easily understandable representation of relative frequencies, especially useful when communicating statistical findings to a broad audience or when comparing parts of a whole dataset.\n\n

Real Limits

The boundaries of intervals for continuous variables that indicate the range for which a score can actually fall.

Nominal Scale

A scale of measurement used for categorical data without a defined order.

Ordinal Scale

A scale of measurement where categories are ordered but the distances between them are not measurable.

Interval Scale

A scale of measurement with equal intervals between values, but no true zero.

Ratio Scale

A scale of measurement similar to interval but with a meaningful zero point.

Histogram

A graphical representation of data that displays the frequency of scores within specified intervals.

Frequency Distribution Polygon

A graph created by plotting dots for each frequency and connecting them with a line.

Bar Graph

A graph that represents categorical data with rectangular bars with lengths proportional to the values they represent.

Symmetrical Distribution

A distribution where each side is a mirror image of the other.

Skewed Distribution

A distribution where scores pile up on one side and taper off on the other side, can be positive or negative.

Continuous Variables

Variables that can take on an infinite number of values within a given range.

Discrete Variables

Variables that can take on a finite number of values.