中文说明： 为了建立一种有效的机器学习的解决方案，您需要为您的系统性能评价的适当的分析工具。交叉验证是系统的最重要的工具之一，它给你诚实的评估你的真实准确性。 此外，如果您的系统，你必须手动选择有参数，您可以经常选择最好的价值解析通过尝试不同的值，由此产生的交叉验证精度比较。
English Description：
In order to build an effective machine learning solution, you will need the proper analytical tools for evaluating the performance of your system. Cross-validation is one of the most important tools, as it gives you an honest assessment of the true accuracy of your system. Also, if there are parameters in your system that you have to select manually, you can often choose the best value analytically by tryin