习题 2.1考察14个不同桑品种4个桑叶的理化性状为总含氮量(x1,%)、可容性糖(x2,%)、叶绿素含 x3,%)、单叶面积重(x4,g/100cm2)及万头产茧层量(y)。算得相关系数如下表,试作通径分析。 各变量的简单相关系数(r)、平均数(x)及标准差(S) 1.000000.744770.48664-0.590030.85756 x20.744771.000000.35944 0.537880.86001 0.486640.359441.00000 0.466420.51885 x4-0.59003-0.53788-0.466421.00000-0.73517 0.857560.86001 0.51885 0.735171.00000 x 13.3657 1.125 2.4479 s0.167884.152830.140480.18179193.2566 (答案:Py1=0.33892,Py2=0.4381,Py3=0.07242,Py=0.26539,R2=0.9007 2.2测得某猪场50头肥猪5项胴体性状瘦肉量(y,kg)、眼肌面积(Ⅺ,cm2)、腿肉量(X2,kg)、 腰肉量(X3,kg)、椎骨数(X4,个)的资料如下,试作逐步通径分析 15.0223.735.491.212814.2625.264.161.5529 12.6223.344.321.353015.5029.995.261.7429 14.8628.845 13.9827.674.721.492914.6525.064.751.6529 15.9120.835.351.562914.12|17.994.451.7426 12.4722.274.271.502915.4028.495.331.7128 15.8027.575.251.852815.0427.324.951.6729 14.3228.014.621.512916.7422.235.672.302 13.7624.794.421.4 17.13|30.435.671.9 15.1828.965.301.662813.1221.294.741.2028 14.2025.774.871.642815.19|27.295.021.8329 17.0723.175.801.902814.2618.93|4.611.4 15.4028575221.663015.0925.265.18|1.5028 15.9423.525.181.982614.75|23.844.751.792 14.3321.864.861.592917.7636.545.901.8730 15.1128.955.181.3728|16.7828.325.311.8830 13.8124.534.881.392714.0121.664.841.6327 15.5827.65502|1.66|2914.8526.91492|1.22 15.8527.295.551.702814.4518.594.851.4526 15.2829.075.261.822812.6823.554.061.4128 16.4032.475.81.752915.0126.375.121.7029 15.0229.655.081.702913.8922.754.841.4729 15.7322.114.901.813015.9530.735.701.7929 14.7522.434651.822813.0624.544.251.092919 习题 2.1 考察 14 个不同桑品种 4 个桑叶的理化性状为总含氮量（x1，%）、可容性糖（x2，%）、叶绿素含 量（x3，%）、单叶面积重（x4，g/100cm2）及万头产茧层量（y）。算得相关系数如下表，试作通径分析。 各变量的简单相关系数（rij）、平均数（ x ）及标准差（S） rij x1 x2 x3 x4 y x1 1.00000 0.74477 0.48664 -0.59003 0.85756 x2 0.74477 1.00000 0.35944 -0.53788 0.86001 x3 0.48664 0.35944 1.00000 -0.46642 0.51885 x4 -0.59003 -0.53788 -0.46642 1.00000 -0.73517 y 0.85756 0.86001 0.51885 -0.73517 1.00000 x 5.38 13.3657 1.125 2.4479 2611 S 0.16788 4.15283 0.14048 0.18179 193.2566 （答案：Py.1=0.33892，Py.2=0.43881，Py.3=0.07242，Py.4=-0.26539，R 2=0.9007） 2.2 测得某猪场 50 头肥猪 5 项胴体性状瘦肉量（y，kg）、眼肌面积（X1，cm2）、腿肉量（X2，kg）、 腰肉量（X3，kg）、椎骨数（X4，个）的资料如下，试作逐步通径分析。 y X1 X2 X3 X4 y X1 X2 X3 X4 15.02 23.73 5.49 1.21 28 14.26 25.26 4.16 1.55 29 12.62 23.34 4.32 1.35 30 15.50 29.99 5.26 1.74 29 14.86 28.84 5.04 1.92 29 14.44 17.92 5.02 1.28 29 13.98 27.67 4.72 1.49 29 14.65 25.06 4.75 1.65 29 15.91 20.83 5.35 1.56 29 14.12 17.99 4.45 1.74 26 12.47 22.27 4.27 1.50 29 15.40 28.49 5.33 1.71 28 15.80 27.57 5.25 1.85 28 15.04 27.32 4.95 1.67 29 14.32 28.01 4.62 1.51 29 16.74 22.23 5.67 2.30 28 13.76 24.79 4.42 1.46 29 17.13 30.43 5.67 1.96 30 15.18 28.96 5.30 1.66 28 13.12 21.29 4.74 1.20 28 14.20 25.77 4.87 1.64 28 15.19 27.29 5.02 1.83 29 17.07 23.17 5.80 1.90 28 14.26 18.93 4.61 1.45 28 15.40 28.57 5.22 1.66 30 15.09 25.26 5.18 1.50 28 15.94 23.52 5.18 1.98 26 14.75 23.84 4.75 1.79 28 14.33 21.86 4.86 1.59 29 17.76 36.54 5.90 1.87 30 15.11 28.95 5.18 1.37 28 16.78 28.32 5.31 1.88 30 13.81 24.53 4.88 1.39 27 14.01 21.66 4.84 1.63 27 15.58 27.65 5.02 1.66 29 14.85 26.91 4.92 1.22 29 15.85 27.29 5.55 1.70 28 14.45 18.59 4.85 1.45 26 15.28 29.07 5.26 1.82 28 12.68 23.55 4.06 1.41 28 16.40 32.47 5.18 1.75 29 15.01 26.37 5.12 1.70 29 15.02 29.65 5.08 1.70 29 13.89 22.75 4.84 1.47 29 15.73 22.11 4.90 1.81 30 15.95 30.73 5.70 1.79 29 14.75 22.43 4.65 1.82 28 13.06 24.54 4.25 1.09 29