Re: Bootstrap question

From: Nick Holford n.holford@auckland.ac.nz Subject: Re: [NMusers] Bootstrap question Date: Tue, 26 Sep 2006 10:40:52 +1200 Mark, Your responses are too short for me to understand why bias in a bootstrap CI is important in these cases. Can you explain in each case (with an explicit example) why you think bias would be important and giving an idea of what magnitude of bias you would consider important? It should be kept firmly in mind that CIs obtained with the asymptotic standard error method are likely to be biased because 1) they are asymptotic and 2) the CI calculation nearly always is based on assuming a normal distribution and thus symmetry of the interval. Nick -- Nick Holford, Dept Pharmacology & Clinical Pharmacology University of Auckland, 85 Park Rd, Private Bag 92019, Auckland, New Zealand email:n.holford@auckland.ac.nz tel:+64(9)373-7599x86730 fax:373-7556 http://www.health.auckland.ac.nz/pharmacology/staff/nholford/ _______________________________________________________