Information Technology Journal1812-56381812-5646Asian Network for Scientific Information10.3923/itj.2011.2024.2033YijunLiu MingfangZhu JialiTang GuangpingZhu HongfenJiang 1120111011Homeotic Gene Expression Programming (H-GEP) is a kind of Gene Expression Programming (GEP) which infuses homeotic genes into the chromosome to achieve a new mapping from the biological mechanisms to the GEP coding. Present study makes a further study on H-GEP. At first we analyze the expression space of the H-GEP individual. Secondly, an algorithm named HNEC is presented which computes the value of the expression encoded by an H-GEP individual without building an expression tree and expression. Thirdly, the performance and characteristic of the H-GEP method for function discovery are studied. Providing a complex and flexible way to link sub functions to form the target function, H-GEP is superior in discovery of complex functions. Fourthly, we study the effect of normal gene number on H-GEP performance. Finally, one application of H-GEP in the area of environmental quality assessment is presented.]]>Ferreira, C.,20011387129Tang, C., L. Duan, J. Peng, H. Zhang and Y. Zhong,20062006Zhu, M.F., C.J. Tang, S.J. Qiao, S.C. Dai and Y. Chen,201047292299Cheng, Z. and C. Zhi-hua, 20073613191321Zuo, J., C.J. Tang, C. Li, C.A. Yuan and A.L. Chen,200431295564Duan, L., C.J. Tang, J. Zuo, Y. Chen, Y.X. Zhong and C. Yuan,20044116841689Xiaodong, H., T. Changjie, L. Zhi, P. Donghang and L. Yong,20041596105Lin, Y.S., L.P. Hong and W. Jia,20082921112114Peng, J., C.J. Tang, C. Li and J.J. Hu,20052814591466Shucheng, D., T. Changjie, Z. Mingfang and C. Yu,200840121126Qichang, F.,2005Datong, X. and C. Qiaoyun, 200834210213Jiang, D., Z. Wu, Z. Jian, K. Lishan, T. Ming-Duan and L. Kang-Shun,20061814661468Mo, H.F. and L.S. Kang,20082028282831Yong, C., L. Jian and W. Changqing,200945209211Yijun, L., G. Chunsheng, Z. Guangping, J. Hongfen and C. Dan,20109213216, (In Chinese)Ferreira, C.,20062nd Edn.,pp: 3-116pp: 3-116