Lecture 11: Normal Distribution and z Scores

Flashcards covering key vocabulary related to Normal Distribution and z Scores.

Normal Distribution

A probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean.

z Score

A statistical measurement that describes a value's relation to the mean of a group of values, measured in terms of standard deviations from the mean.

Empirical Rule

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

Standard Deviation (σ)

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

Mean (μ)

The average of a set of numbers, calculated by dividing the sum of the numbers by the count of the numbers.

Unit Normal Table (UNT)

A table that shows the percentage of values to the left of a given z score in a standard normal distribution.

Probability

The measure of the likelihood that an event will occur, expressed as a ratio of the number of favorable outcomes to the total number of outcomes.

Area Under the Curve

In probability and statistics, the area under a probability density function curve represents the probability of the random variable falling within a certain range.

Raw Score

The original measurement or data point before any transformations or z score calculations are applied.

Proportion

A part, share, or number considered in relation to a whole which expresses the fraction of a total.