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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
nprandom.seed # Setting seed for reproducibility
samplesize
data nprandom.normalloc scale sizesamplesize
#Next, we'll define functions to calculate the loglikelihood, estimate parameters mu and sigma and the gradient matrix:
# Loglikelihood function for centered normal distribution
def loglikelihoodparams data:
mu sigmasq params
n lendata
loglikelihood n nplog nppi sigmasq sigmasq npsumdata mu
return loglikelihood
# Estimation of parameters using maximum likelihood estimation
def estimateparametersdata:
# Initial guess for parameters
initialguess npmeandata npvardata
result minimizeloglikelihood, initialguess, argsdata methodLBFGSB
return result.x
# Calculate the gradient matrix
def gradientmatrixparams data:
mu sigmasq params
n lendata
gradmu sigmasq npsumdata mu
gradsigmasq n sigmasq sigmasq npsumdata mu
return nparraygradmu gradsigmasq
#Now, let's estimate parameters from the simulated data:
# Estimate parameters using MLE
estimatedparams estimateparametersdata
muestimate, sigmasqestimate estimatedparams
printEstimated mu: muestimate
printEstimated sigma: sigmasqestimate
#Following that, we'll calculate the gradient matrix:
# Calculate the gradient matrix
gradient gradientmatrixestimatedparams, data
printGradient matrix:"
printgradient
from scipy import optimize
from scipy import stats
#Finally, we'll conduct the LR Wald, and LM tests:
# Likelihood ratio test
lrstat loglikelihoodestimatedparams, data loglikelihood data
lrpvalue stats.chicdflrstat, df #degrees of freedom
# Wald test
invhessian minimizeloglikelihood, estimatedparams, argsdata methodLBFGSB jacTruehessinv
waldstat npdotgradient npdotinvhessian, gradient
waldpvalue stats.chicdfwaldstat, df # degrees of freedom
# Lagrange Multiplier test
lmstat npdotgradient gradient
lmpvalue stats.chicdflmstat, df # degrees of freedom
printLikelihood Ratio test pvalue:", lrpvalue
printWald test pvalue:", waldpvalue
printLagrange Multiplier test pvalue:", lmpvalue
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