An asset bubble has a number of features. Mansharamani outlines features that should be looked for to recognize a bubble.
Features of the classic bubble:
(1) widespread participation
(2) prices go up without an anchor in objective reality (higher prices increase demand)
(3) behavior (overconfidence, deaf to skeptics, different this time)
(4) use of leverage
(5) support from the regulatory environment and/or moral hazard
An asset bubble usually occurs during a mania.
