Density Curves & Normal Distributions

These flashcards cover key concepts related to density curves and normal distributions that are essential for understanding the underlying principles in statistics.

Density Curve

A mathematical model representing the distribution of a continuous variable, used for smooth approximation.

Mean

The average value of a dataset, calculated as the sum of all values divided by the number of values.

Median

The middle value in a dataset when values are arranged in ascending order.

Variance

A measure of the spread of a set of values, defined as the average of the squared deviations from the mean.

Standard Deviation

A measure that quantifies the amount of variation or dispersion in a set of values.

Normal Distribution

A symmetric, bell-shaped distribution defined by its mean (µ) and standard deviation (σ), where data points are more concentrated around the mean.

Z-score

A statistical measure that describes a value's relation to the mean of a group of values, expressed in standard deviations.

68-95-99.7 Rule

A statistical rule that states that for a normal distribution, approximately 68% of values fall within one standard deviation of the mean, 95% within two, and 99.7% within three.

Standard Normal Distribution

A normal distribution with a mean of 0 and a standard deviation of 1, used as a reference for determining probabilities.

Uniform Distribution

A type of distribution in which all outcomes are equally likely, leading to a rectangular shape.

Triangular Distribution

A continuous probability distribution shaped like a triangle, defined by a lower limit, upper limit, and a peak.