A Fabella Is a Small Bone in the Knee Found

question 37

Short Answer

A fabella is a small bone in the knee found in a tendon behind the femur in some species of mammals, including humans. Historically, it has been rare, but recently it has become more common. Probability data for birth year and presence or absence of the bone is presented in the table. Imagine we examined 200 skeletons of individuals born in 1900 and 100 skeletons of individuals born in 2000. Draw a probability tree diagram depicting the probabilities of a random individual from our study having or not having a fabella in their skeleton.
​
Probability that skeleton will have a fabella.

$\begin{array}{lc}\text { Birth year and } \\\text { fabella status } & \text { Probability } \\\hline 1900, \text { absent } & 0.80 \\1900, \text { present } & 0.20 \\2000 \text {, absent } & 0.60 \\2000, \text { present } & 0.40\end{array}$

---

Definitions:

Rational Consumers

Individuals who make decisions to maximize their utility or satisfaction based on the information available and their own preferences.

Marginal Utility

The change in total satisfaction or utility that a consumer experiences as a result of consuming one additional unit of a good or service.

Framing Effects

The influence on an individual's decision-making caused by the way information is presented, rather than just the information itself.

Status Quo

The existing state of affairs; in prospect theory, the current situation from which gains and losses are calculated.