Based on high resolution experimental maps of nucleosome positioning of the human,yeast,C.elegans and Drosophila,the nucleosome positioning mechanisms were elucidated by using Increment of Diversity combined with Quadratic Discriminant analysis model (IDQD)[1],Position-Correlation Scoring Function (PCSF) model[2],information content model[3],dynamic energy-based model[4].All these classifiers can distinguish nucleosome core DNA sequence and linker DNA sequence with high accuracy.The models successfully identified genome-wide nucleosome-enriched or nucleosome-depleted regions.The theoretical predictions were verified for GAA triplet-repeats-containing sequences and artificial designed R5Y5 sequences by using the salt-dialysis method[5].