is a part of our everyday lives. Everyday we make
judgements based on probability:
Although we assign certain probabilities to certain events, others might assign different probabilities to those same events due to their difference of opinion. For example, not everyone agrees with the high chance of the Bulls winning the game. They might say that there is a 20% chance the Bulls will win the game tomorrow. It all depends on what the person believes. Chance may result from human design such as casino games and the lottery, or it may result from nature such as determining a persons sex and other human characteristics. Probability is defined as the branch of mathematics that describes the pattern of chance outcomes.
|Probability originated from the study of games of chance. Tossing a dice or spinning a roulette wheel are examples of deliberate randomization that are similar to random sampling. Games of chance were not studied by mathematicians until the sixteenth and seventeenth centuries. Probability theory as a branch of mathematics arose in the seventeenth century when French gamblers asked Blaise Pascal and Pierre de Fermat (both well known pioneers in mathematics) for help in their gambling. In the eighteenth and nineteenth centuries, careful measurements in astronomy and surveying led to further advances in probability. In the twentieth century probability is used to control the flow of traffic through a highway system, a telephone interchange, or a computer processor; find the genetic makeup of individuals or populations; figure out the energy states of subatomic particles; Estimate the spread of rumors; and predict the rate of return in risky investments.|
The time an object takes to hit the ground from a certain height can easily be predicted using simple physics. The position of asteroids in three years from now can also be predicted using advanced technology.
Not everything in life, however, can be predicted using science and technology. For example, a toss of a coin may result in either a head or a tail. Also, the sex of a new-born baby may turn out to be male or female. In these cases, the individual outcomes are uncertain. With experience and enough repetition, however, a regular pattern of outcomes can be seen (by which certain predictions can be made). For example, the result of the next 100 tosses of a coin can be assumed to be 50 heads and 50 tails. Since there are only two possible outcomes, the chances of getting a head or a tail are equal. This describes the basis of the Random Phenomenon:
|An event or
phenomenon is called random if individual outcomes are
uncertain but there is, however, a regular distribution
of relative frequencies in a large number of repetitions.
For example, after tossing a coin a significant number of
times, it can be seen that about half the time, the coin
lands on the head side and about half the time it lands
on the tail side.
Note of interest: At around 1900, an English statistician named Karl Pearson literally tossed a coin 24,000 times resulting in 12,012 heads thus having a relative frequency of 0.5005 (His results were only 12 tosses off from being perfect!).