Probability
Probability is the measure of uncertainty of various phenomenon , numerically . It can have positive value from 0 to 1 .
The words ‘ probably ’, ‘ doubt ’, ‘ most probably ’, ‘ chances ’, etc ., used in the statements above involve an element of uncertainty .
Concept of Probability is used in insurance industry to calculate the premium ; it is also used in stock markets , gambling industry , weather forecasting , manufacturing industry , Science Experiments etc .
Probability is a measure of uncertainty of various phenomenon . Probability = ( no . of favourable outcome )/ ( total no . of outcomes ) Approach to Probability : o o o
Statistical approach : Observation & data collection Classical approach : Only Equal probable events
Axiomatic approach : For real life events . It closely relates to set theory .
In this chapter we will focus on Axiomatic Approach to Probability .
Sample space : Set of all possible outcomes of a random experiment is called sample space . It is denoted by the symbol S . Example : In Toss of a coin , Sample space is Head , Tail .
Sample point : Each element of the sample space is called a sample point . E . g . in throw of Die , Head is a Sample point .
Event : It is the set of favourable outcome . Also , Event is a subset of the sample space . E . g . Event of getting odd outcome in a throw of a die
Types of Event o o o
Impossible and Sure Events Simple Event Compound Event