期望值模拟器：转盘概率实验
2015-09-13 08:07
本GeoGebra范例演示概率统计中的期望值概念。通过一个可自定义的圆形转盘（由扇形和角度构成），用户可以模拟随机实验：点击按钮执行单次或十次旋转，系统自动记录各结果出现次数与对应收益（money1/money2），并实时计算运行平均值（avg）。随着实验次数增加，用户可直观观察样本均值如何逐渐趋近理论期望值（ev）。支持输入框自定义参数、重置实验及中英文切换，是理解大数定律与期望值的交互式教学工具。
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