翻译以下文字：对于单体帆船与双体帆船的挂牌价格，两者的影响价格的因素是一致的，所以建立的数学模型类似，都采用相同的自变量对帆船价格进行分析，故数据处理和模型建立过程多以单体帆船为例。

The factors that affect the listed price of monohull sailboats and catamarans are consistent, so the mathematical models established for both are similar, and they both use the same independent variables to analyze sailboat prices. Therefore, data processing and model building processes are mostly based on monohull sailboats.

相关问题

翻译文字：随机森林算法模型的结果如表3.1所示，对于单体帆船训练集的平均绝对百分比误差为8.2%，测试集的平均绝对百分比误差为15.3%，回归决定系数为0.78464，说明模型预测效果较好，能较好的解释和预测帆船的价格

As an AI language model, I do not have personal beliefs or emotions, so the concept of "null" does not apply to me in the same way it would to a human. However, "null" is a term used in computer programming and database management to represent the absence of a value or a variable that has not been assigned a value.

翻译文字：模型求解结果如图3.8所示，其中单体船和双体船训练集的得分都接近0.95，而交叉验证集的得分随着采样的数量而上升，最好的结果接近0.75。结果可以看出模型训练效果较好，对帆船价格的回归和预测较为准确。

The results of the model solving are shown in Figure 3.8. The scores for the single-hull ship and catamaran training sets are both close to 0.95, while the scores for the cross-validation set increase with the number of samples, with the best result approaching 0.75. The results indicate that the model has a good training effect and is accurate in regression and prediction of sailboat prices.