Skip to main content
Article thumbnail
Location of Repository

Should We Take Measurements At an Intermediate Design Point?

By Andrew Gelman


It is well known that, for estimating a linear treatment effect with constant variance, the optimal design divides the units equally between the two extremes of the design space. If the dose-response relation may be nonlinear, however, intermediate measurements may be useful in order to estimate the effects of partial treatments. We consider the decision of whether to gather data at an intermediate design point: do the gains from learning about nonlinearity outweigh the loss in efficiency in estimating the linear effect? Under reasonable assumptions about nonlinearity, we find that, unless sample size is very large, the design with no interior measurements is best, because with moderate total sample sizes, any nonlinearity in the doseresponse will be difficult to detect. We discuss in the context of a simplified version of the problem that motivated this work---a study of pest-control treatments intended to reduce asthma symptoms in children. Keywords: asthma, Bayesian infer..

Topics: asthma, Bayesian inference, dose response experimental design, pest control, statistical significance
Year: 2000
OAI identifier: oai:CiteSeerX.psu:
Provided by: CiteSeerX
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • (external link)
  • (external link)
  • Suggested articles

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.