Bias is a term frequently used in forecasting and six sigma. Bias is the term used when a consistent deviation occurs from the mean/average. The deviation is always in one direction (either high deviation or low deviation). When forecasting a zero bias would represent a perfect forecast. In six sigma 0 deviation would represent absolutely no deviation from the established standard.
The bullwhip effect can be described as an extreme change in the supply chain upstream that is normally triggered by a small change in demand downstream. This often affects inventory levels which can shift from being on backorder to being in excess of the needed demand. The general cause of these fluctuations within the supply chain is almost always related to communication. As communication travels up the supply chain with various forms of waste and delay amounts, times and the accuracy tend to "whip" further from the actual need. The one sure fire way to eliminate the bullwhip effect is to align supply with demand, including completely transparent communication and synchronization of the supply chain perfectly.
Reference: Apics Dictionary 2015 - Bullwhip effect.
When you buff a car you place a thin layer of wax on the paint of the car. This glossy wax helps protect the car's paint and body against elements like wind, weather and changes in environmental conditions. Similarly buffer inventory is meant to help keep productions lines steady when changes in demand occur. Some common examples of buffer inventory are:
Reference: Apics Dictionary 14'th Edition
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