An event is usually called a fact or phenomenon that has occurred or may actually occur, in reality. Events are regular and random. With natural events, we can accurately say how and why they occurred, what caused them to occur and what the consequences will be, as well as with what order, i.e. regularity they will be repeated. Examples of natural events are physical or chemical experiments that, with repeated repetitions, give the same result.
Random events are a more complex phenomenon. Because they are called random, it is difficult to predict when, under what conditions they will occur and whether they will occur at all. For example, two people live in one city, in one microdistrict, get to the place of work by one mode of transport, and even at about the same time. It is only natural that one day they will meet. And, on the contrary, if people live far from each other, there are practically no points of contact between them, a lot of coincidences must coincide so that they once collide. The task is complicated if one of them belongs to the social lower classes of society, and the other is at the top level of the social ladder. The probability of a random event, i.e. their meetings, in this situation, is zero.
At the same time, when tossing a coin many times, the number of “tails” will be approximately the same as the number of “eagles”. Probability theory is investigating the possibility of repeating the same phenomena.
Random events are one of the main concepts used by probability theory. These are the very events that may occur as a result of some experience or in the process thereof.
Probability theory divides events into three types:
- reliable events. They necessarily occur when they produce the same experience, and their result can be predicted in advance. We can say for sure that if you leave wet white linen in the cold, moisture will freeze out of it, and the material will bleach even cleaner;
- the event is impossible. It will not happen during this experiment, no matter how much you try. For example, when hydrogen and oxygen atoms are combined in the appropriate proportion, apple juice will never work , but only water;
- random events - the pattern of their manifestation is difficult to predict.
Among random events, you can also distinguish your own groups and combinations.
Types of random events:
- incompatible. These include those that cannot occur in one trial or experiment. For example, when tossing a coin, either only “eagle” or only “tails” can fall out, but both sides never. Or: a person cannot sleep and stay awake at the same time; in nature, day and night does not come simultaneously;
- compatible events. These include those that can occur simultaneously. For example, in the summer the sun can shine and rain is falling at the same time - it is also called blind. Also, at the same time, a person can read and eat food, etc. The main thing here is that these events do not contradict each other;
- the so-called full group of events. It includes such events, one of which is manifested during the experiment. For example, a student has credit. And here the following scenarios are possible: the student will pass the test, which will be noted in the record; the student will fail the test, which is also noted in his book; the student will come to the standings;
- equally possible events - the probability of one event occurring is equal to the chance of another event occurring, etc. So the chances of a greater number of “tails” are equal to the chances of falling more “eagles”.
Random events and the probability of their occurrence are determined by certain mathematical formulas.