The planet occurrence rate for multiple stars is important in two aspects .
First , almost half of stellar systems in the solar neighborhood are multiple systems .
Second , the comparison of the planet occurrence rate for multiple stars to that for single stars sheds light on the influence of stellar multiplicity on planet formation and evolution .
We developed a method of distinguishing planet occurrence rates for single and multiple stars .
From a sample of 138 bright ( K _ { P } < 13.5 ) Kepler multi-planet candidate systems , we compared the stellar multiplicity rate of these planet host stars to that of field stars .
Using dynamical stability analyses and archival Doppler measurements , we find that the stellar multiplicity rate of planet host stars is significantly lower than field stars for semi-major axes less than 20 AU , suggesting that planet formation and evolution are suppressed by the presence of a close-in companion star at these separations .
The influence of stellar multiplicity at larger separations is uncertain because of search incompleteness due to a limited Doppler observation time baseline and a lack of high resolution imaging observation .
We calculated the planet confidence for the sample of mutlti-planet candidates , and find that the planet confidences for KOI 82.01 , KOI 115.01 , KOI 282.01 and KOI 1781.02 are higher than 99.7 % and thus validate the planetary nature of these four planet candidates .
This sample of bright Kepler multi-planet candidates with refined stellar and orbital parameters , planet confidence estimation , and nearby stellar companion identification offers a well-characterized sample for future theoretical and observational study .