Available Chlorine

Keywords: nonlinear regression, pure error, goodness of fit

Description

The data are from a Proctor and Gamble study reported by Smith and Dubey (1964) on the amount of available chlorine in a product as a function of time since manufacture. Theoretical considerations lead to the model

Chlorine = a + (0.49 - a) exp{ -b (Weeks - 8) }


	Variable		Description

	Weeks		Time in weeks since manufacture
	Chlorine		Available chlorine

Download

Data File (tab-delimited text)

Source

Jennrich, R. I., and Bright, P. B. (1976). Fitting systems of linear differential equations using computer generated exact derivatives. Technometrics 18, 385-392.

Jennrich, R. I. (1995). An Introduction to Computational Statistics. Prentice-Hall, Englewood Cliffs, New Jersey. Section 8.2.1.

Analysis

The plot gives the data and the theoretical curve fitted by least squares:

Chlorine vs Weeks with fitted curve (10109 bytes)