集中趋势：CEO薪酬均值中位数众数

def solve():
    import pandas as pd
    import matplotlib.pyplot as plt
    url = 'https://data.zuihe.com/wooldridge/ceosal1.csv'
    df = pd.read_csv(url)
    mean = df['salary'].mean()
    median = df['salary'].median()
    mode = df['salary'].mode()[0]
    print(f'均值: {mean:.1f}')
    print(f'中位数: {median:.1f}')
    print(f'众数: {mode:.1f}')
    df['salary'].hist(bins=30, color='steelblue', edgecolor='black', alpha=0.7)
    plt.axvline(mean, color='red', ls='--', label=f'均值={mean:.0f}')
    plt.axvline(median, color='green', ls='--', label=f'中位数={median:.0f}')
    plt.axvline(mode, color='orange', ls='--', label=f'众数={mode:.0f}')
    plt.legend(); plt.xlabel('CEO年薪'); plt.title('CEO薪酬分布')
    plt.tight_layout(); plt.show()
    print('结论：分布右偏，中位数更适合代表典型CEO薪酬')