Binary logarithm team sits out the second round). The same number of rounds is also necessary to determine a clear winner in a Swiss-system tournament. In photography, exposure values are measured in terms of the binary logarithm of the amount of light reaching the film or sensor, in accordance with the Weber–Fechner law describing a logarithmic response of the human visual system to light. A single stop of exposure is one unit on a base- logarithmic scale. More precisely, the exposure value of a photograph is defined as where is the f-number measuring the aperture of the lens during the exposure, and
The purpose of a system is what it does or sheer ignorance of circumstances." The term is widely used by systems theorists. It is generally invoked to counter the notion that the purpose of a system can be read from the intentions of those who design, operate, or promote it. From a cybernetic perspective complex systems are not controllable by simple notions of management, and interventions in a system can best be understood by looking at how they affect observed system behavior. When "side effects" or "unintended consequences" reveal that system behavior is poorly understood, then taking the POSIWID perspective allows the more political understandings of system behavior to