Performing montecarlo simulation of regression coefficients

Steps:

  1. Random Sampling: Randomly select 100 pairs of discharge (Q) and suspended sediment concentration (C) from the dataset. Convert these values to their logarithmic forms: log(Q) and log(C).
  2. Compute the Slope (b) of the Regression Line:
    • Calculate the covariance between log(Q) and log(C).
    • Calculate the variance of log(Q).
    • Compute the slope as: b=Cov(logQ,logC)Var(logQ)b = \frac{\text{Cov}(\log Q, \log C)}{\text{Var}(\log Q)}
  3. Compute the Intercept (logA) of the Regression Line:
    • Compute the mean of log(C) and log(Q).
    • Calculate the intercept using the equation: logA=Mean(logC)(b×Mean(logQ))\log A = \text{Mean}(\log C) - (b \times \text{Mean}(\log Q))
  4. Compute the Coefficient of Determination (R2R^2):
    • Compute the Pearson correlation coefficient rr between log(Q) and log(C): r=Cov(logQ,logC)σlogQσlogCr = \frac{\text{Cov}(\log Q, \log C)}{\sigma_{\log Q} \cdot \sigma_{\log C}}
    • Compute R2R^2 as the square of the Pearson correlation coefficient: R2=r2R^2 = r^2
  5. Repeat Steps 1–4, 5000 Times:
    • Store the computed slope (b), intercept (logA\log A), and coefficient of determination (R2R^2) for each iteration.
  6. Plot the Relationship:
    • Convert the stored intercept values back to the original scale: A=10logAA = 10^{\log A}
    • Plot b (slope) vs. A (10intercept^\text{intercept}) to analyze their relationship.

This version ensures mathematical correctness and clarity. Let me know if you'd like further refinements!

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