PLS方法的思想早在上个世纪30年代就已经产生，但是在上世纪三十年代至六十年代中期这段时间，PLS方法尚未形成系统、完整的理论与算法。-PLS method of thinking as early as 30 years in the last century has been produced, but in the mid-thirties to six this time, PLS method system, a complete theory and algorithms have not yet formed.