  Whether radio intermediate quasars possess relativistic jets as radio-loud
quasars is an important issue in the understanding of the origin of radio
emission in quasars. In this letter, using the two-epoch radio data obtained
during Faint Image of Radio Sky at Twenty centimeter sky (FIRST) and NOAO VLA
Sky Survey (NVSS), we identify 89 radio variable sources in the Sloan Digital
Sky Survey. Among them, more than half are radio intermediate quasars
(RL=f2cm/f2500A<250). For all objects with available multiple band radio
observations, the radio spectra are either flat or inverted. The brightness
temperature inferred from the variability is larger than the synchrotron-self
Compton limit for a stationary source in 87 objects, indicating of relativistic
beaming. Considering the sample selection and viewing angle effect, we conclude
that relativistic jets probably exist in a substantianl fraction of radio
intermediate quasars.
