Basic Probability and Discrete Probability Distributions

  • Basic Probability Concepts
  • Understanding of probability fundamentals, including:
    • Probability: Numerical representation (0 to 1) of the possibility of an event occurring.
    • Event: Outcome of a variable.
  • Approaches to Assessing Probability
  • A priori Classical Probability: Based on prior knowledge.
  • Empirical Classical Probability: Based on observed data.
  • Subjective Probability: Based on personal judgment.
  • Types of Events
  • Simple Event: One characteristic outcome.
  • Complement of an Event (A'): Outcomes not part of event A.
  • Joint Event (A ∩ B): Two or more characteristics occurring simultaneously.
  • Mutually Exclusive Events: Events that cannot occur together (e.g., Male vs. Female).
  • Collectively Exhaustive Events: One event must occur (e.g., loyalty program member vs. non-member).
  • Probability Calculations
  • Joint Probability: P(A and B).
  • Marginal Probability: P(A).
  • General Addition Rule: P(A or B) = P(A) + P(B) - P(A and B).
  • Conditional Probability: P(A | B), the probability of A given B has occurred.
  • Decision Trees: Alternative to contingency tables for visualizing probabilities.
  • Statistical Independence: Events A and B are independent if the occurrence of one does not affect the other.
  • Counting Rules: Methods to calculate possible outcomes.
  • Rule 1: Outcomes for k mutually exclusive events over n trials.
  • Rule 2: Outcomes for k1, k2, … kn events across trials.
  • Rule 3: Arrangements of n items: n!.
  • Rule 4: Permutations of X from n objects.
  • Rule 5: Combinations of X from n objects ignoring order.
  • Discrete Probability Distributions
  • Defines expectations and variances for discrete outcomes.
  • Expected Value (Mean) Calculation: E(X) = sum of values x their probabilities.
  • Variance and Standard Deviation Definitions and Calculations.
  • Portfolio Calculations for expected return and risk using weight averages.