NOTES

1. The measurements from separate experiments can be considered as a sample from an infinite population of possible measurements; and, likewise, the means of any series of measurements are a sample from the possible means of samples of measurements from the whole population. The distribution of the sample means is called the sampling distribution of the mean: its mean is the same as the mean of the original population. The standard error of the mean (SEM) is equivalent to the standard deviation of the sampling distribution of the mean (Miller and Miller 1993). The standard error of the mean can also be determined from the relationship between the standard deviation of the individual measurements, ς, and the sample size, n, following the equation: SEM = ς / √n, and this method has been used here.

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AUTHOR INFORMATION

ALAN PHENIX was educated at Leeds University, United Kingdom, receiving a B.Sc. Honors in chemistry and color chemistry combined in 1979. He studied conservation of easel paintings for three years at the Courtauld Institute of Art, University of London, and was awarded the institute's postgraduate diploma in 1984. After an internship at Tate Gallery, London, he worked as a paintings conservator in Australia, returning to Britain in 1989 to take up a teaching and research position at the Hamilton Kerr Institute, University of Cambridge. He was a lecturer in the Department of Conservation and Technology at the Courtauld Institute of Art from 1991 to 2000, during which time he spent 15 months on secondment to the MOLART (Molecular Aspects of Aging in Painted Works of Art) project managed by the Foundation for Fundamental Research on Matter, Institute for Atomic and Molecular Physics (FOM-AMOLF), Amsterdam. During 2001 he was research fellow at the Royal College of Art, London, and he has recently been appointed associate professor at the Institute for Archaeology, Art History and Conservation at the University of Oslo. He is presently coordinator of the ICOM-CC Working Group Paintings 1: Conservation and Restoration of Paintings. Address: Department of Conservation Studies, Institute for Archaeology, Art History and Conservation (IAKK), University of Oslo, Frederiks gt. 3, 0164 Oslo, Norway.