Statistics for Programmers-Table of Contents
It is a memo of the definition of the word about "event".
An event is what happens as a result of an attempt. For example, the result of an experiment (trial) on what to roll a dice is called an event.
All possible events. Often represented by omega.
Example) All events when throwing dice
\Omega = \{1, 2, 3, 4, 5, 6\}
Events that can be decomposed
Example) An event in which an even number appears by rolling the dice This is a compound event because it can still be decomposed into 2,4,6.
G = \{2, 4, 6\}
Events that cannot be decomposed any further
Example) In the case of dice, each of the 1st to 6th rolls is an elementary event.
"Except when there is" event
Example) When the event that an even number appears by rolling the dice is A, the odd numbered roll becomes a complementary event as shown below.
A^c = \{1, 3, 5\}
When the complementary events and compound events are added, it becomes all events.
\Omega = A + A^c = {1, 2, 3, 4, 5, 6}
An event that does not exist. Speaking of dice, a 7 is rolled.
An event that cannot occur at the same time. You can have odd-numbered eyes and even-numbered eyes at the same time.
Of the two events A and B, the event where ʻA or B` occurs
The formula is as follows. A or B
A ∪ B
∪ is called a" cup ".
Example) An event in which an even number or a dice can be divided by 3
G = {2, 3, 4, 6}
Of the two events A and B, events where A and B occur at the same time
The formula is as follows. A and B
A ∩ B
∩ is called a hat.
Example) An even number of dice that can be divided by 3
G = {6}
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