Both Ricoh WG-50 and Samsung Galaxy Camera 2 have 16.0 MP resolution sensors but Ricoh WG-50's sensor is (1/2. ) and Samsung Galaxy Camera 2's sensor is 1/2.3-inch (6.17 x 4.55 mm ).
Since Samsung Galaxy Camera 2's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Ricoh WG-50.
Below you can see the WG-50 and Galaxy Camera 2 sensor size comparison.
As seen above, Samsung Galaxy Camera 2 has a infx Larger sensor area than Ricoh WG-50. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.