Harry Haupt, Joachim Schnurbus, and Rolf Tschernig, "On Nonparametric Estimation of a Hedonic Price Function", Journal of Applied Econometrics, Vol. 25, No. 5, 2010, pp. 894-901. This paper uses the data set that appeared in Paul Anglin and Ramazan Gencay, "Semiparametric Estimation of a Hedonic Price Function", Journal of Applied Econometrics, Vol. 11, No. 6, 1996, pp. 633-648. and Christopher Parmeter, Daniel Henderson, and Subal Kumbhakar, "Nonparametric Estimation of a Hedonic Price Function", Journal of Applied Econometrics, Vol. 22, No. 3, 2007, pp. 695-699. See http://www.econ.queensu.ca/jae/1996-v11.6/anglin-gencay/readme.ag.txt for a description of the data, which are in the file http://www.econ.queensu.ca/jae/1996-v11.6/anglin-gencay/ag-data.zip and the readme of the Parameter et al. (2007) paper http://www.econ.queensu.ca/jae/2007-v22.3/parmeter-henderson-kumbhakar/readme.phk.txt