Standard t-tests can be severely biased in the presence of trended reg
ressors and serially correlated errors. Veall (Economics Letters, 1986
, 21, 41-44) presented simulation evidence that traditional bootstrapp
ing does not substantially reduce this bias. Subsequent research has d
eveloped a number of refinements to the bootstrap including accelerate
d bias correction, prepivoting and iterated bootstrapping. The models
considered by Veall were re-examined employing these refinements. It w
as found that substantial improvements are possible, particularly from
prepivoting and iterated bootstrapping.