Zhang, DandanChen, ChunlaiSheng, Yu2015-08-102015-08-101756-137Xhttp://hdl.handle.net/1885/14654PURPOSE – The purpose of this paper is to analyze the effects of public investment in agricultural R&D and extension on broadacre farming productivity in Australia. DESIGN/METHODOLOGY/APPROACH – An autoregressive integrated moving average (ARIMA) regression model is applied to estimate the effects of public investment in agricultural R&D and extension on Australian braodacre productivity. FINDINGS– The study reveals that public investment in agricultural R&D and extension has contributed almost two-thirds of average annual broadacre productivity growth between 1952-1953 and 2006-2007, the average internal rate of return to public investment in agricultural R&D and extension was 28.4 and 47.5 per cent a year, respectively, and overseas spill-ins is an important source of domestic agricultural productivity growth. PRACTICAL IMPLICATIONS – Policy implications: the findings suggest that increasing public investment in agricultural R&D and extension and maintaining agricultural R&D policy stability are equally important to have a sustained long-term agricultural productivity growth, and maintaining an open trade and investment regime is important to benefit from foreign knowledge spillovers which is especially important for developing countries. ORIGINALITY/VALUE – This paper contributes to the existing literature by employing more sophisticated econometric techniques with an extended data set for the period from 1952-1953 to 2006-2007. The study separates the contribution of public R&D investment and the extension investment, and also takes into account the contribution of overseas public investment on the TFP growth in the Australian broadacre sector.16© Emerald Group Publishing Limited http://www.sherpa.ac.uk/romeo/issn/1756-137X/Voluntary deposit by author of author's pre-print or author's post-print allowed on author's personal website or Institutional repository (Sherpa/Romeo as of 23/10/2015).AustraliaAgricultureTotal factor productivityPublic R&D2015-02-0210.1108/CAER-05-2014-00522016-06-14