Figure of merit

A figure of merit is a quantity used to characterize the performance of a device, system or method, relative to its alternatives. In engineering, figures of merit are often defined for particular materials or devices in order to determine their relative utility for an application. In commerce, such figures are often used as a marketing tool to convince consumers to choose a particular brand.

Examples

• Clock rate of a CPU
• Calories per serving
• Contrast ratio of an LCD
• Frequency response of a speaker
• Fill factor of a solar panel
• Resolution of the CCD in a digital camera
• Detection performance of a sonar system
• Noise figure of a radio receiver
• The thermoelectric figure of merit, Z, a material constant proportional to the efficiency of a thermoelectric couple made with the material
• The figure of merit of digital-to-analog converter (DAC) is calculated as (Power dissipation)/((2^ENOB) * Effective Bandwidth) [J/Hz].
• Luminous efficacy of lighting
• Battery life of a laptop computer ^[1]

Benchmarks are synthetic figures of merit that summarize the speed of computers in performing various typical tasks. Benchmarks designed by a manufacturer generally rate the manufacturer's products more favorably than benchmarks designed by others or by independent benchmarkers.

Deception

The precision and verifiability of numbers sometimes make them a more effective sales tool than vague and non numeric descriptions such as "state of the art" or "leaves the others in the dust". When used in deceptive advertising, the deception lies more in the question of relevance rather than truth since the number quoted as a figure of merit may not be enough to determine performance when comparing products. For example, when purchasing a laptop a consumer could choose based on the capacity of its hard drive. The rpm, cache, and seek times may not be noted, but significantly affect performance.

Some figures such as Peak Music Power are used in selling consumer merchandise and have the principal merit of yielding high numbers that can impress people who don't know what the numbers mean. Other figures such as Specific Fuel Consumption are addressed to engineers and other studious buyers whom the sellers dare not mislead.

Another example is the megapixel count of a digital camera. A consumer unaware that the number of pixels on a sensor is only one indication of the quality of the image that is captured may, for example, buy a camera with more pixels squeezed onto a small sensor, thus losing quality to small pixels.

References

This marketing-related article is a stub. You can help Wikipedia by expanding it.