教育回报学术回归图（学术图表）

def solve():
    import pandas as pd
    import matplotlib.pyplot as plt
    import numpy as np
    
    url = 'https://liangdaima.com/static/data/wooldridge/wage1.csv'
    df = pd.read_csv(url)
    
    from scipy import stats
    plt.rcParams['font.size'] = 12
    slope, intercept, r_value, p_value, std_err = stats.linregress(df['educ'], df['wage'])
    x_line = np.linspace(df['educ'].min(), df['educ'].max(), 100)
    y_pred = slope * x_line + intercept
    plt.figure(figsize=(10,6))
    plt.scatter(df['educ'], df['wage'], alpha=0.3, color='black', s=20)
    plt.plot(x_line, y_pred, 'k-', linewidth=2)
    plt.fill_between(x_line, y_pred - 1.96*std_err*20, y_pred + 1.96*std_err*20, alpha=0.2, color='black')
    plt.text(14, df['wage'].max()*0.8, f'wage = {intercept:.2f} + {slope:.2f} x educ
R^2 = {r_value**2:.3f}', fontsize=11)
    plt.title('教育年限与工资', fontsize=14)
    plt.xlabel('教育年限', fontsize=12)
    plt.ylabel('工资', fontsize=12)
    plt.grid(alpha=0.3)
    plt.tight_layout()
    plt.show()
    return "可视化代码执行完成"