Random experiment

Random experiment- is a process or procedure, repeatable under basically the same condition, leading to well-defined
outcomes. It is random because we can never tell in advance what the realization is going to be even if we can specify
what the possible outcomes are:

Example 1:
Consider the process of tossing an ordinary coin once. It is a random experiment because it is a process. We can repeat
the tossing of coin under basically the same environmental conditions. This repetition is commonly called trial. When
the coin is tossed once we can tell in advance that the coin will land with face head up or face tail up. Ignoring the
unusual possibility that the coin will land on its edge. In simple terms, we can say that the possible outcomes are head
or tail. This experiment has been considered as a classic example.
While everyone can understand what experiment is, few realize that this simple examples serves as a model for real-world
phenomena where there are only two possible outcomes. Some examples are the following:
- the sex of unborn child is either a male or a female;
- a student will either pass or fail a subject; and
- a business will either profit or loss.

Example 2:

Consider the experiment of recording the number of cars pulling up at a sevice station for gasoline per day. This is random
experiment because recording is a process. The process can be repeated tomorrow or next week. We know that on any day there
will be no customer or one or two, and so on.

Example 3:

An agriculturist may be interested in the yield of a new variety of rice.  He plants this variety in a field and records the
yield in Kg/ha. This is a random experiment because planting and recording of the yield can eventually be repeated in a
different farm or in another season.  In any trial, the reseacher knows that the yield will be zero (if a storm wiped out
the crop) or it can be any positive number.

Further Definitions(taken from http://www.mathgoodies.com/)   
An experiment is a situation involving chance or probability that leads to results called outcomes.   
Example: In the problem above, the experiment is spinning the spinner.
An outcome is the result of a single trial of an experiment.   
Example: The possible outcomes are landing on yellow, blue, green or red.
An event is one or more outcomes of an experiment.   
Example:One event of this experiment is landing on blue.
Probability is the measure of how likely an event is.   
Example: The probability of landing on blue is one fourth.

Fill in the blank by indicating if the case is an experiment, outcome, event, or probability.

________1. Tossing a coin
________2. Rolling a double 6-sided die
________3. Choosing a marble from a jar
________4. Rolling a pair of dice
________5. Landing on blue
________6. choosing 3 marbles from a jar
________7. Choose a number at random from 1 to 5
________8. Choose a letter at random from the word LOVE
________9. 1/2 chances of getting the correct answer.
________10. 1/6 chances of getting the number 6 in a 6-sided die.

Elementary Statistic by Reyes C.Z & Saren L.L.


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