Such volcanoes are devastating, but very rare. The last one happened at Toba in Sumatra, Indonesia, 74,000 years ago. The active volcanic system at Yellowstone National Park has resulted in super-eruptions-the most recent happened 640,000 years ago. Yellowstone's volcanism is powered by magma rising from a hotspot.
A biased opinion is based on a preconceived notion or idea about a thing, person or group of people based on personal beliefs. In psychology, a bias is known as a cognitive shortcut.. It is based on the idea that the human brain, in order to conserve energy, naturally looks for shorter paths to conclusions by using what has been ingrained to draw speedy conclusions.
Medical Definition of Bias. Bias: 1. When a point of view prevents impartial judgment on issues relating to the subject of that point of view. In a clinical trial, bias refers to effects that a conclusion that may be incorrect as, for example, when a researcher or patient knows what treatment is being given. To avoid bias, a blinded study may be done. 2. Deviation of results or inferences from the truth, or processes leading to such systematic deviation.