ENGR 100 Lecture Notes - Lecture 23: Observational Error, Voltmeter, Random Effects Model
Document Summary
Classification of uncertainties into systematic and random effects. Correct use of words accuracy, precision, bias. How to write inexact quantities using engineering and other notation. A property of a physical object that can be represented using a real number (e. g. , t, p, p) As opposed to counting, measurement is not exact. An interval around estimate in which true value lies, this is called the uncertainty interval. True value measured value = measurement error. Also called a bias or an offset. Error has same magnitude and sign when repeated measurements are made under same conditions. E. g. temperature changes affect electronic components and measuring instruments. Correction factor can be applied to compensate. Caused by imperfection in adjustments or construction of instrument. E. g. in repeated measurements, an observer may. Exert slightly different pressures on a micrometer. Connect voltmeter leads in slightly different locations. They produce both positive and negative errors wit zero mean value.
