Discrete-time forward interest rate curve models are studied, where the curves are driven by a random field. Under the assumption of no-arbitrage, the maximum likelihood estimator of the volatility parameter is given and its asymptotic behaviour is studied. First, the so-called martingale models are examined, but we will also deal with the general case, where we include the market price of risk in the discount factor.
József Gáll. Gyula Pap. Martien C. A. van Zuijlen. "Maximum likelihood estimator of the volatility of forward rates driven by geometric spatial AR sheet." J. Appl. Math. 2004 (4) 293 - 309, 26 September 2004. https://doi.org/10.1155/S1110757X04306133