  I measure the physical properties of 38 transiting extrasolar planetary
systems, bringing the total number studied within the Homogeneous Studies
project to 82. Transit light curves are modelled using JKTEBOP, with careful
attention paid to limb darkening, eccentricity and third light. The physical
properties of each system are obtained from the photometric parameters,
published spectroscopic measurements and five sets of theoretical stellar model
predictions. Statistical errors are assessed using Monte Carlo and
residual-permutation algorithms and propagated via a perturbation algorithm.
Systematic errors are estimated from the interagreement between results
calculated using five theoretical stellar models. The headline result is a
major upward revision of the radius of the planet in the OGLE-TR-56 system,
from 1.23-1.38 Rjup to 1.734 +/- 0.051 +/- 0.029 Rjup (statistical and
systematic errors, respectively). Its density is three times lower than
previously thought. This change comes from the first complete analysis of
published high-quality photometry. Significantly larger planetary radii are
also found for Kepler-15, KOI-428, WASP-13, WASP-14 and WASP-21 compared to
previous work. I present the first results based on Kepler short-cadence data
for Kepler-14, Kepler-15 and KOI-135. More extensive long-cadence data s used
to improve the measured properties of KOI-196, KOI-204, KOI-254, KOI-423 and
KOI-428. Detailed analyses are given for HAT-P-3, HAT-P-6, HAT-P-9, HAT-P-14
and WASP-12, based on more extensive datasets than considered in previous
studies. I revisit the correlations between orbital period and surface gravity,
and orbital period and mass of the transiting planets, finding both to be
significant at the 4 sigma level. I conclude by discussing the opportunities
for follow-up observations, the sky positions and the discovery rate of the
known transiting planets.
