probability mass function
nounUK /ˌprɒbəˈbɪləti mæs ˈfʌŋkʃən/
US /ˌprɑːbəˈbɪləti mæs ˈfʌŋkʃən/
A math rule that tells you how likely each exact result is when you roll a dice or pick a card.
The probability mass function shows that a fair coin lands on heads half the time.
SYNONYMS
OTHER MEANINGS
2. A function that gives the probability that a discrete random variable is exactly equal to some value.
For a six-sided die, the probability mass function assigns 1/6 to each face.
3. A way to list all possible separate outcomes of an experiment together with their chances.
The teacher drew the probability mass function on the board to show the chances of each score.
4. A mathematical tool used in statistics to describe countable results like the number of heads in ten coin flips.
We used a probability mass function to model how many customers arrive each hour.