###Instruction: Multi-class classification, answer with one of the labels:['no_consensus', 'delete', 'keep', 'comment', 'merge', 'redirect'] : ###Input:  Q5961678: Kerr effect (Q5961678) : change in refractive index of a material in response to an applied electric field : ( delete | history | links | entity usage | logs ) Merged with Q883038 Merging Hafez 's contributions. Ārash ツ ‏ 17:10, 12 September 2013 (UTC)