Occam's razor meets WMAP

Abstract

Using a variety of quantitative implementations of Occam's razor we examine the low quadrupole, the 'axis of evil' effect and other detections recently made appealing to the excellent Wilkinson Microwave Anisotropy Probe (WMAP) data. We find that some razors fully demolish the much lauded claims for departures from scale-invariance. They all reduce to pathetic levels the evidence for a low quadrupole (or any other low ℓ cut-off), both in the first and third year WMAP releases. The 'axis of evil' effect is the only anomaly examined here that survives the humiliations of Occam's razor, and even then in the category of 'strong' rather than 'decisive' evidence. Statistical considerations aside, differences between the various renditions of the data sets remain worrying. © 2007 The Authors. Journal compilation © 2007 RAS.