Final answer:
A probability density function (PDF) must satisfy certain conditions, including being integrated to zero over its entire range, integrating to one, being non-negative for all values, and being continuous.
Step-by-step explanation:
A probability density function (PDF) is a function that describes the likelihood of a random variable taking on particular values. To be a valid PDF:
- a) ∫f(x) dx = 0: The integral of the PDF over its entire range should be equal to zero. This means that there is no probability associated with any single point.
- b) ∫f(x) dx = 1: The integral of the PDF over its entire range should be equal to one. This ensures that the probabilities of all possible outcomes collectively add up to one.
- c) f(x) ≥ 0 for all x: The PDF must be non-negative for all possible values of the random variable. Negative probabilities are not meaningful.
- d) f(x) is continuous for all x: The PDF should be a continuous function, meaning that there are no jumps or discontinuities in its graph.