  The Fermi Large Area Telescope (LAT) has observed more than a hundred of
gamma-ray pulsars, about one third of which are radio-quiet, i.e. not detected
at radio frequencies. The most of radio-loud pulsars are detected by Fermi LAT
by using the radio timing models, while the radio-quiet ones are discovered in
a blind search. The difference in the techniques introduces an observational
selection bias and, consequently, the direct comparison of populations is
complicated. In order to produce an unbiased sample, we perform a blind search
of gamma-ray pulsations using Fermi-LAT data alone. No radio data or
observations at optical or X-ray frequencies are involved in the search
process. We produce a gamma-ray selected catalog of 25 non-recycled gamma-ray
pulsars found in a blind search, including 16 radio-quiet and 9 radio-loud
pulsars. This results in the direct measurement of the fraction of radio-quiet
pulsars $\varepsilon_{RQ} = 64\pm 10\%$, which is in agreement with the
existing estimates from the population modeling in the outer magnetosphere
model. The Polar cap models are disfavored due to a lower expected fraction and
the prediction of age dependence. The age, gamma-ray energy flux, spin-down
luminosity and sky location distributions of the radio-loud and radio-quiet
pulsars from the catalog do not demonstrate any statistically significant
difference. The results indicate that the radio-quiet and radio-loud pulsars
belong to one and the same population. The catalog shows no evidence for the
radio beam evolution.
