STK_SAMPLING_OLHS generates a random Orthogonal Latin Hypercube (OLH) sample CALL: X = stk_sampling_olhs (N) generates a random Orthogonal Latin Hypercube (OLH) sample X, using the construction of Ye (1998). The algorithm only works for sample sizes N of the form 2^(R+1)+1, with R >= 1. Trying to generate an OLHS with a value of N that is not of this form generates an error. The number of factors is D = 2*R, and the OLHS is defined on [-1; 1]^D. CALL: X = stk_sampling_olhs (N, D) does exactly the same thing, provided that there exists an integer R such that N = 2^(R+1)+1 and D = 2*R (or D is empty). CALL: X = stk_sampling_olhs (N, D, BOX) generates an OLHS on BOX. Again, D can be empty since the number of factors can be deduced from N. CALL: X = stk_sampling_olhs (N, D, BOX, PERMUT) uses a given permutation PERMUT, instead of a random permutation, to initialize the construction of Ye (1998). As a result, the generated OLHS is not random anymore. PERMUT must be a permutation of 1:2^R. If BOX is empty, then the default domain [-1, 1]^D is used. NOTE: orthogonality The samples generated by this functions are only orthogonal, stricty- speaking, if BOX is a symmetric domain (e.g., [-1, 1] ^ D). Otherwise, the generated samples should be called "uncorrelated". REFERENCE Kenny Q. Ye, "Orthogonal Column Latin Hypercubes and Their Application in Computer Experiments", Journal of the American Statistical Association, 93(444), 1430-1439, 1998. http://dx.doi.org/10.1080/01621459.1998.10473803 See also: stk_sampling_randomlhs, stk_sampling_maximinlhs
Package: stk