概率论与数理统计公式（Probability theory and mathematical statistics formula）.docVIP

概率论与数理统计公式（Probability theory and mathematical statistics formula） The first chapter stochastic events and their probability (1) permutations and combinations formulas are used to pick out the possible number of permutations of n individuals from m individuals. The number of possible combinations of n individuals selected from m individuals. (2) addition and multiplication principle addition principle (two methods can complete the matter): m+n The two method can be used to complete a certain subject. The first method can be completed by M methods, and the second method can be completed by n methods. Then, this method can be completed by m+n methods. Multiplication principle (two steps can not do this separately): m x n The first step can be completed by M methods, and the second step can be completed by n methods, and this can be accomplished by m * n methods in two ways. (3) some common permutations are repetitive and non repetitive (ordered) Opposite events (at least one) Order problem (4) random test and random events if a test is repeated in the same conditions, and each time the test results may be more than one, but before a test is not to assert that it appears which results, said the study was a randomized trial. The possible outcome of the experiment is called a random event. (5) basic events, sample spaces and events in a test, regardless of the number of events, can always find such a group of events, it has the following properties: Each trial must occur and only one event in this group occurs; Any event is made up of some of the events in this group. Each event in such a group of events is called a basic event, which is used to represent the event. The whole of the basic event is called the sample space of the test. An event is a collection of parts (basic events) in it. Capital letters A, B, C are usually used,... Representing events, they are subsets. Is it an inevitable event, an impossible one?. The probability of an impossible event is zero, and t