The magnitude-frequency distribution (MFD) describes the relative proportion of earthquake magnitudes and provides vital information for seismic hazard assessment. The b-value, derived from the MFD, is commonly used to estimate the probability that a future earthquake will exceed a specified magnitude threshold. Improved MFD and b-value estimates are of great importance in the central and eastern United States where high volumes of fluid injection have contributed to a significant rise in seismicity over the last decade. In this study we provide new MFD and b-value estimates for the 2011 Prague, Oklahoma sequence using a relative magnitude approach that depends only on waveform data to recalculate magnitudes. We recalculate the magnitudes of 8775 events that occurred between March 2010 and March 2012 and find that the distribution of relative magnitudes exhibits less curvature than the MFD of cataloged magnitudes. We also compare the distribution of successive magnitudes differences to the traditional MFD and show that a combination of the magnitude difference distribution (MDFD) and relative magnitudes yields the most stable estimate of b-value. Using the MDFD and relative magnitudes, we examine the temporal and spatial variations in the b-value and observe low b-values during the aftershock sequence for at least 5 months after the M5.7 mainshock, though areas surrounding the northeast part of the sequence experience elevated b-values. These new estimates of MFD and b-value will contribute to further hazard assessment for induced earthquake sequences and promote discussion regarding the use of b-value to understand the evolution of induced seismic sequences.