Context : The spin state of small asteroids can change on a long timescale by the Yarkovsky-O ’ Keefe-Radzievskii-Paddack ( YORP ) effect , the net torque that arises from anisotropically scattered sunlight and proper thermal radiation from an irregularly-shaped asteroid . The secular change in the rotation period caused by the YORP effect can be detected by analysis of asteroid photometric lightcurves . Aims : We analyzed photometric lightcurves of near-Earth asteroids ( 1865 ) Cerberus , ( 2100 ) Ra-Shalom , and ( 3103 ) Eger with the aim to detect possible deviations from the constant rotation caused by the YORP effect . Methods : We carried out new photometric observations of the three asteroids , combined the new lightcurves with archived data , and used the lightcurve inversion method to model the asteroid shape , pole direction , and rotation rate . The YORP effect was modeled as a linear change in the rotation rate in time \mathrm { d } \omega / \mathrm { d } t . Values of \mathrm { d } \omega / \mathrm { d } t derived from observations were compared with the values predicted by theory . Results : We derived physical models for all three asteroids . We had to model Eger as a nonconvex body because the convex model failed to fit the lightcurves observed at high phase angles . We probably detected the acceleration of the rotation rate of Eger \mathrm { d } \omega / \mathrm { d } t = ( 1.4 \pm 0.6 ) \times 10 ^ { -8 } \mathrm { rad } \mathrm% { d } ^ { -2 } ( 3 \sigma error ) , which corresponds to a decrease in the rotation period by 4.2 \mathrm { ms } \mathrm { yr } ^ { -1 } . The photometry of Cerberus and Ra-Shalom was consistent with a constant-period model , and no secular change in the spin rate was detected . We could only constrain maximum values of | \mathrm { d } \omega / \mathrm { d } t| < 8 \times 10 ^ { -9 } \mathrm { rad } \mathrm { d } ^ { -2 } for Cerberus , and | \mathrm { d } \omega / \mathrm { d } t| < 3 \times 10 ^ { -8 } \mathrm { rad } \mathrm { d } ^ { -2 } for Ra-Shalom . Conclusions :