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The program does not work. Can you help me fix it ? # First, we'll simulate a dataset following a centered normal distribution: import numpy

The program does not work. Can you help me fix it? # First, we'll simulate a dataset following a centered normal distribution:
import numpy as np
from scipy.optimize import minimize
# Simulate data following a centered normal distribution
np.random.seed(42) # Setting seed for reproducibility
sample_size =1000
data = np.random.normal(loc=0, scale=1, size=sample_size)
#Next, we'll define functions to calculate the log-likelihood, estimate parameters (mu and sigma^2), and the gradient matrix:
# Log-likelihood function for centered normal distribution
def log_likelihood(params, data):
mu, sigma_sq = params
n = len(data)
log_likelihood =-(n /2)* np.log(2* np.pi * sigma_sq)-(1/(2* sigma_sq))* np.sum((data - mu)**2)
return -log_likelihood
# Estimation of parameters using maximum likelihood estimation
def estimate_parameters(data):
# Initial guess for parameters
initial_guess =[np.mean(data), np.var(data)]
result = minimize(log_likelihood, initial_guess, args=(data,), method='L-BFGS-B')
return result.x
# Calculate the gradient matrix
def gradient_matrix(params, data):
mu, sigma_sq = params
n = len(data)
grad_mu =(1/ sigma_sq)* np.sum(data - mu)
grad_sigma_sq =-(n /(2* sigma_sq))+(1/(2* sigma_sq **2))* np.sum((data - mu)**2)
return np.array([grad_mu, grad_sigma_sq])
#Now, let's estimate parameters from the simulated data:
# Estimate parameters using MLE
estimated_params = estimate_parameters(data)
mu_estimate, sigma_sq_estimate = estimated_params
print("Estimated mu:", mu_estimate)
print("Estimated sigma^2:", sigma_sq_estimate)
#Following that, we'll calculate the gradient matrix:
# Calculate the gradient matrix
gradient = gradient_matrix(estimated_params, data)
print("Gradient matrix:")
print(gradient)
from scipy import optimize
from scipy import stats
#Finally, we'll conduct the LR, Wald, and LM tests:
# Likelihood ratio test
lr_stat =2*(log_likelihood(estimated_params, data)- log_likelihood([0,1], data))
lr_p_value =1- stats.chi2.cdf(lr_stat, df=2) #degrees of freedom =2
# Wald test
inv_hessian = minimize(log_likelihood, estimated_params, args=(data,), method='L-BFGS-B', jac=True).hess_inv
wald_stat = np.dot(gradient, np.dot(inv_hessian, gradient))
wald_p_value =1- stats.chi2.cdf(wald_stat, df=2) # degrees of freedom =2
# Lagrange Multiplier test
lm_stat = np.dot(gradient, gradient)
lm_p_value =1- stats.chi2.cdf(lm_stat, df=2) # degrees of freedom =2
print("Likelihood Ratio test p-value:", lr_p_value)
print("Wald test p-value:", wald_p_value)
print("Lagrange Multiplier test p-value:", lm_p_value)

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