Polarization of the Si II λ6355 Å absorption feature compared with potentially correlated parameters. Wang et al. (2007) claimed a correlation between PSi II and peak width (upper left panel). It has been suggested that there is a correlation between PSi II and the equivalent width of the Si II λ6355 Å absorption feature (upper right panel). Maund et al. (2010) claimed a correlation between PSi II and the velocity gradient of the Si II λ6355 Å absorption feature (lower left panel). Maund et al. (2010) also investigated claims of a correlation between PSi II and the nebular velocity of the emission feature, [Fe II] 7155 Å (lower right panel). The filled boxes show our measured values for SN 2011fe. The range in polarization reflects the difference between the −5 day polarization and the maximum measured polarization. The range in peak width and ﹩{\dot{v}}_{\mathrm{Si}{\rm{II}}}﹩ are from the literature. The range in vNEB is from the minimum and maximum measured in our Epoch 5–7 nebular spectra. Non-2011fe data are from Wang et al. (2007), Pereira et al. (2013), Silverman et al. (2012), Hachinger et al. (2006), and Maund et al. (2010) and references therein.