  The Machina thought experiments pose to major non-expected utility models
challenges that are similar to those posed by the Ellsberg thought experiments
to subjective expected utility theory (SEUT). We test human choices in the
`Ellsberg three-color example', confirming typical ambiguity aversion patterns,
and the `Machina 50/51 and reflection examples', partially confirming the
preferences hypothesized by Machina. Then, we show that a quantum-theoretic
framework for decision-making under uncertainty recently elaborated by some of
us allows faithful modeling of all data on the Ellsberg and Machina paradox
situations. In the quantum-theoretic framework subjective probabilities are
represented by quantum probabilities, while quantum state transformations
enable representations of ambiguity aversion and subjective attitudes toward
it.
