Dois tipos de probabilidade

Daniel Sanches explica:

Class Probability and Case Probability

According to Mises, there are two approaches that the human mind can take concerning incomplete knowledge of real affairs: class probability and case probability.
The most important thing to note about this distinction is that class probability has to do with frequency, and case probability does not. Another important thing to note is that class probability has to do with causality and nature, while case probability has to do with teleology and human choice.[5]
Mises defines the two kinds of probability in Human Action.

Class probability means: We know or assume to know, with regard to the problem concerned, everything about the behavior of a whole class of events or phenomena; but about the actual singular events or phenomena we know nothing but that they are elements of this class.[6]

Case probability means: We know, with regard to a particular event, some of the factors which determine its outcome; but there are other determining factors about which we know nothing.[7]

Here are some examples Mises gives of each type.

Class Probability	Case Probability
Gambling (Lottery Tickets, Roulette, etc.)	Betting (Sports Wagers, Political Bets, etc.)
Engineering Margins and Medical Prognoses	Historical Scholarship
Business-Inventory Vicissitudes	Entrepreneurial Speculation
Purchasing Insurance