This paper presents bounds on convergence rates of Markov chains in terms o
f quantities calculable directly from chain transition operators. Bounds ar
e constructed by creating a probability distribution that minorizes the tra
nsition kernel over some region, and by examining bounds on an expectation
conditional on lying within and without this region. These are shown to be
sharper in most cares than previous similar results. These bounds are appli
ed to a Markov chain useful in frequentist conditional inference in canonic
al generalized linear models.