Is there any concrete examples of a null event
I interpreted a line of reasoning in a book on probability, on the null set being an event of every experiment.
Sample space are defined as a set of all possible outcomes of an experiment. Events are subsets of a sample space.
The null set is a subset of every set. A Sample space is a set. Hence, the null set is a subset of a sample space.
The null set is an event of any experiment.
I can not find a concrete example of a null event. Take a coin toss; would the null event be not tossing the coin at all? It does not make any sense to me. So, is there any concrete examples of a null event.
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$\begingroup$You want the intersection of two events to be an event, so that you can talk of the probability of A and B happening. And this means that you must include the empty set, since that's the intersection of two disjoint sets. For example, if you flip a coin, what is the probability of getting both head and tails at the same time? Answer: Zero, since it's an impossible event (corresponding to the empty set in the sample space).
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