design the function function tn= true_negative(sens, spec, prior) that calculates the probability of a negative test to be correct bayes in matlab

main.m
function tn = true_negative(sens, spec, prior)
% Calculates the probability of a negative test to be correct using Bayes theory
% sens: sensitivity of the test
% spec: specificity of the test
% prior: prior probability of a negative test

% Complementary probabilities
comp_sens = 1 - sens;
comp_spec = 1 - spec;
comp_prior = 1 - prior;

% Bayes' formula
tn = (comp_sens * prior) / ((comp_sens * prior) + (comp_spec * comp_prior));
end
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The function true_negative takes the sensitivity sens, specificity spec and the prior probability of a negative test prior as input and outputs the probability of a negative test being true. The formula used is the Bayes' theorem where comp_sens, comp_spec and comp_prior are the complementary probabilities of sensitivity, specificity and prior respectively. The result tn is calculated with Bayes' formula where tn is the probability of a negative test being true.

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