STAT 301 Lecture Notes - Probability Distribution
Document Summary
Way to summarize the relationship between two variables/events. A population distribution is a way of assigning probabilities to all possible values (or categories) of a variable. Population distributions for categorical variables are summarized in relative frequency bar charts. For numeric discrete data, summarized in relative frequency histograms. For numeric continuous, summarized in a density histogram. Generally, we use smoothed histograms to show population distributions. For density histograms, this is called a density curve. The total area under the curve is 1. The area under the curve and within any particular interval is interpreted as the probability of observing a value in the corresponding interval when an object is selected at random from the population. For a continuous numeric variable x and any particular numbers a and b. P(a < x < b) = p(x < b) p(x < a) In a continuous distribution, p(x = a) = 0.
