DEFINITION of 'Unconditional Probability'
The probability that an event will occur, not contingent on any prior or related results. An unconditional probability is the independent chance that a single outcome results from a sample of possible outcomes. To find the unconditional probability of an event, sum the outcomes of the event and divide by the total number of possible outcomes.
Also referred to as marginal probability.
INVESTOPEDIA EXPLAINS 'Unconditional Probability'
Conditional probability measures the chance of an occurrence ignoring any knowledge gained from previous or external events. Since this probability ignores new information, it remains constant. For example, let's examine a group of stocks. A stock can either be a winner, which earns a positive income, or a loser, which has a negative income. Out of five stocks, stock A and B are winners, while C, D and E are losers. What is the unconditional probability of choosing a winning stock? Since two outcomes out of a possible five will produce a winner, the unconditional probability is 40% ( 2 / 5 ).

Symmetrical Distribution
A situation in which the values of variables occur at regular ... 
Default Probability
The degree of likelihood that the borrower of a loan or debt ... 
Volatility
1. A statistical measure of the dispersion of returns for a given ... 
A Priori Probability
Probability calculated by logically examining existing information. ... 
Value At Risk  VaR
A statistical technique used to measure and quantify the level ... 
Risk
The chance that an investment's actual return will be different ...

Fundamental Analysis
Find The Right Fit With Probability Distributions
Discover a few of the most popular probability distributions and how to calculate them. 
Mutual Funds & ETFs
5 Ways To Measure Mutual Fund Risk
These statistical measurements highlight how to mitigate risk and increase rewards. 
Bonds & Fixed Income
Find The Highest Returns With The Sharpe Ratio
Learn how to follow the efficient frontier to increase your chances of successful investing. 
Active Trading Fundamentals
Bet Smarter With The Monte Carlo Simulation
This technique can reduce uncertainty in estimating future outcomes. 
Active Trading Fundamentals
How To Convert Value At Risk To Different Time Periods
Volatility is not the only way to measure risk. Learn about the "new science of risk management". 
Options & Futures
An Introduction To Value at Risk (VAR)
Volatility is not the only way to measure risk. Learn about the "new science of risk management". 
Fundamental Analysis
Monte Carlo Simulation With GBM
Learn to predict future events through a series of random trials. 
Investing
How to Use Stratified Random Sampling
Stratified random sampling is a technique best used with a sample population easily broken into distinct subgroups. Samples are then taken from each subgroup based on the ratio of the subgroup’s ... 
Economics
How A Limited Government Affects A Country's Finances
Countries with limited governments have fewer laws about what individuals and businesses can and can’t do. What's the net result? 
Fundamental Analysis
Lognormal and Normal Distribution
When and why do you use lognormal distribution or normal distribution for analyzing securities? Lognormal for stocks, normal for portfolio returns.