The generation of random numbers has many uses (mostly in statistics, for random sampling, and simulation). Before modern computing, researchers requiring random numbers would either generate them through various means (dice, cards, roulette wheels, etc.) or use existing random number tables.
Yawning, swallowing or chewing helps open the small canal (Eustachian tube) which connects your middle ear in the inner side of the ear drum, and equalizes the pressure with the outer side and causes the sensation of ears popping when swallowing.
A yawn, swallowing, or chewing gum can relieve pressure in the ear by briefly opening the Eustachian Tube and allowing the pressure inside the ear to equalize with the outside. In most cases, ear fullness is caused by something as simple as congestion from a cold or hay fever, a mild infection, or even earwax build-up.