  Previous attempts to study the correlation between the transit depth and the
stellar metallicity of Kepler gas giant planets has led to different results. A
weakly significant negative correlation was reported from the Kepler's (Q1-Q12)
gas giant candidates with estimated radii of 5-20R$_\odot$ and [Fe/H] values
taken from the Kepler Input Catalog (KIC). With the release of the last Kepler
catalog (Q1-Q17), we now have the largest homogeneous sample of exoplanets.
This enables a solid statistical analysis of this correlation. In the present
work, we revise this correlation, within a Bayesian framework, for two large
homogeneous samples: confirmed and complete. We expand a Hierarchical model to
account for false positives in the studied samples. Our statistical analysis
reveals no correlation between the transit depth and the stellar metallicity.
The fact that we found no evidence of such correlation will have implications
for planet formation theory and interior structure of giant planets.
