# Quality Assurance Terms Glossary/L

## L

**Law of Averages ** - Says that the average of independent observations of random variables that have the same probability distribution is increasingly likely to be close to the expected value of the random variables as the number of observations grows. More precisely, if x1, x2, x3, . . . , Are independent random variables with the same probability distribution, and e(x) is their common expected value, then for every number e > 0, p{|(x1 + x2 + . . . + Xn)/n ]]</strong> - e(x) | < e} converges to 100% as n grows. This is equivalent to saying that the sequence of sample means x1, (x1+x2)/2, (x1+x2+x3)/3, . . . Converges in probability to e(x).

**Law of Diminishing Marginal Returns ** - A law that stipulates that there is a point at which investment in quality improvement will become uneconomical.

**Leader behaviour ** - A view of leadership stating that leadership potential is related to the behaviours an individual exhibits.

**Leadership ** - The process by which a leader influences a group to move toward the attainment of a group of superordinate goals.

**Leader Skills ** - A view of leadership stating that leadership potential is related to the skills possessed by an individual.

**Leading ** - The power relationship between two or more individuals where the power is distributed unevenly.

**Lean ** - An approach to producing products or services focusing on reducing Total Cycle Time and costs by reducing waste, improving flow, and striving for excellence.

**Lean Enterprise ** - Focusing on the identification and reduction of waste throughout the entire organization and involving both suppliers and customers in the effort.

**Lean Manufacturing** - A manufacturing process involving tools such as value-stream mapping and workflow diagrams without considering either supplier or customer processes. The methodology used to implement the lean production philosophy.

**Learning Curve Effect ** - A theoretical concept that suggests that the more you do something, the better you become at doing it.

**Learning Organization ** - From peter Senge's book the fifth discipline: the art and practice of the learning organization. Senge argues, that to excel in an increasingly complex and dynamic world, organizations will have to provide for and encourage individuals and teams in all levels of the organization to learn. He envisions "learning organizations...Where people continually expand their capacity to create the results they truly desire, where new and expansive patterns of thinking are nurtured, where collective aspiration is set free, and where people are continually learning how to learn together."

**Licensing ** - A method of reaching international markets that does not require the establishment of international supply chains or marketing arms.

**Life Testing ** - A facet of reliability engineering that concerns itself with determining whether a product will fail under controlled conditions during a specified life.

**Linear Regression ** - Fits a line to a scatter-plot in such a way as to minimize the sum of the squares of the residuals.

**Line-Stop Authority ** - The approval authority to stop a production line whenever a problem is detected.

**Logic Flow ** - Often used to refer to the logical sequence of steps in a process.

**Loss to Society ** - According to Taguchi (Taguchi Loss Function), this occurs every time a dimension in a product varies from its target dimension. This is associated with Taguchi’s “ideal quality.”

**Lot ** - A defined quantity of product accumulated under conditions that are considered uniform for sampling purposes

**Lot Tolerance Percent Defective ** aka LTPD - The maximum level of percent defective acceptable in production lots.