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Derivation of Isosceles Trapezoidal Distribution



Raghu N. Kacker, James F. Lawrence


It is known that, if the mid-point of a rectangular distribution is specified, the half-width is inexactly known, and the state of knowledge about the half-width may be represented by a narrower rectangular distribution then the resulting distribution looks like an isosceles trapezoid whose sloping sides are curved (an isocurvilinear trapezoid). What sort of probability distribution must the half-width have for the resulting distribution to be an isosceles trapezoid? We show that if the distribution of the half-width is a variation of the rectangular distribution whose top is sloping (a sloping top distribution) then the resulting distribution is isosceles trapezoid.
Measurement Science and Technology


rectangular distributio, uncertainty in measurement


Kacker, R. and Lawrence, J. (2010), Derivation of Isosceles Trapezoidal Distribution, Measurement Science and Technology, [online], (Accessed July 24, 2024)


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Created December 1, 2010, Updated February 19, 2017