data = data_macpherson2003
data_macpherson2003 returns listener averages of polar error rates (PERs in %) from Macpherson & Middlebrooks (2003).
E. A. Macpherson and J. C. Middlebrooks. Vertical-plane sound localization probed with ripple-spectrum noise. J. Acoust. Soc. Am., 114:430--445, 2003.