4. CONCLUSION 
Although 'hands-on' training in field spectroscopy is essential we believe there is also a role for interactive 
computer-based methods such as the hypertext tutors described here. A systematic empirical study of the errors 
in field spectroscopy such as that described here is just the first step. It is also necessary to model the errors 
numerically so as to address questions of sensitivity. We need to be able to quantify the change in accuracy and 
precision likely to result from a change in atmospheric conditions, or a change in measurement methodology 
for example. Such modelling lends itself well to a computer-based approach such as that described here and 
future work will aim to combine empirically-derived field data and theoretical models of the field measurement 
process. 
Acknowledgements 
Field and workshop assistance from Bill Damon is gratefully acknowledged as is the assistance of David 
Emery in the production of the first NERC-EPFS Tutor. 
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