When is beta distribution bell-shaped or concave? - Cross Validated

Is there some restriction to parameters $( \alpha , \beta)$ that makes the beta distribution concave down? Bell-shaped like e.g. a normal? For example, the cases in purple and black, but not the red

Is a bell curve a parabola? - Quora

The beta distribution

Beta distribution - Wikipedia

beta distribution - Mathematical Definition of Parameters - Cross Validated

What is the intuition behind beta distribution? - Cross Validated

Bell Curve Definition: Normal Distribution Meaning Example in Finance

Beta distribution - Wikipedia

Cutting dynamics research on the five-axis machining of thin curved surface with barrel-taper-ball milling cutter

Design of Physical and Simulation Experiments

Beta distribution - Wikipedia

Three Beta distributions with their parameters

Beta distribution - Wikiwand