[Retracted] Wavelet-Based Multiscale Decomposition Algorithm for Trajectory Capture of Tennis Serves

Table 2

Girls’ serving score ladder.

Ladder division	Shoulder hip twist angle when raising the racket in one shot	Shoulder hip twist angle at first shot	The angle of shoulder-hip twist when raising the racket for the second shot	Shoulder hip twist angle during the second shot
First level ladder	28.315	39.531	28.82	37.25
Secondary ladder	28.645	35.272	39.0968	40.534
Third step	31.517	44.257	28.116	43.766
Fourth step	32.797	36.178	33.954	47.238