Error, Absolute: 

 Error, Accidental : 



Error, Dependent: 



Error, Determinate : 



Error, Independent : 



Error, Indeterminate: 



Error, Instrument: 



Error, Mean: 



Error, Mean Square: 



Error Probable: 



Error, Reading: 



Error, True: 



See Error, True. 



Those deviations, inevitable in all measurements, which re- 

 sult from small unavoidable errors of observation due to 

 more or less fortuitous variation in the sensitivity of our 

 measuring instruments and the keenness of our senses of 

 perception. Such errors are due to the combined effect of 

 a large number of undetermined causes. 



An error produced in a dependent variable by the error of 

 the independent variable. Where Y is a function of X, an 

 error in X will produce an error in Y. Referring to BTgms, 

 where temperatures are a function of depth, an error in 

 depth will produce a corresponding error in temperature. 



An error that is discovered and allowed for in magnitude 

 and sign in the form of a correction allowing for its effect. 



That portion of the error of a dependent variable which in 

 itself is not a function of the error of the independent var- 

 iable; these are accidental errors inherent in the measure- 

 ment of that variable. 



That error which cannot or is not properly allowed for in 

 magnitude and sign. All errors that are not determinate 

 errors. 



Those errors which are specifically related to the measuring 

 instrument. These comprise both determinate errors (some- 

 times called sets) and indeterminate errors (called instrument 

 precision or reproducibility). 



See Deviation, Average. 



See Deviation, Standard. 



An error of such magnitude that from the standpoint of 

 probability the true error of the observation is just as likely 

 to be greater as it is to be less than this magnitude. 

 More generally, it is a measure of the closeness with which 

 the probable value approaches the true value. 



That error introduced into the measurements by the ac- 

 curacy with which the observer can read the measured value 

 of the instruments used to take the measurement. 



The difference between the observed or calculated value and 

 the true value. 



Gaussian Distribution: 

 Geological : 



Gradient: 



See Distribution, Gaussian or Normal. 



Pertaining to the science which treats the history of the 

 earth and its life, or the materials of the earth itself. 

 In Oceanography, geological pertains to the study of the 

 ocean floor formations. 



Rate of change of one dependent variable with respect to 

 the independent variable; slope; first derivative. As applied 

 to BTgm, it is the slope of the curve. 



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