直方图 ni 当xeI,i=1,2,…,k 0, 其他 既是归一化参数，又表示每一组的组距，称为带宽或窗宽， Dissects the range of the data into bins of equal width along the horizontal axis Vertical axis represents the frequency counts(or percents,proportions)-Bars represent the counts Fewer bins,smoother histogram,but less detail about the distribution Trade-off between smoothness and detail:We want to preserve as much detail as possible but we do not want the graph to be too rough(difficult to discern shape) 直方图 • Dissects the range of the data into bins of equal width along the horizontal axis • Vertical axis represents the frequency counts (or percents, proportions)—Bars represent the counts • Fewer bins, smoother histogram, but less detail about the distribution • Trade-off between smoothness and detail: We want to preserve as much detail as possible but we do not want the graph to be too rough (difficult to discern shape)