#include <iostream>
#include <vector>
#include <numeric>
float sum(const std::vector<float> &array)
{
return std::accumulate(array.begin(), array.end(), 0);
}
float square(float x)
{
return x * x;
}
float mean(const std::vector<float> &array)
{
return sum(array) / array.size();
}
float averageSquareDiff(float a, const std::vector<float> &predictions)
{
std::vector<float> results;
for (float x : predictions)
results.push_back(square(x - a));
return mean(results);
}
void diversityTheorem(float truth, const std::vector<float> &predictions)
{
float average = mean(predictions);
std::cout
<< "average-error: " << averageSquareDiff(truth, predictions) << "\n"
<< "crowd-error: " << square(truth - average) << "\n"
<< "diversity: " << averageSquareDiff(average, predictions) << std::endl;
}
int main() {
diversityTheorem(49, {48,47,51});
diversityTheorem(49, {48,47,51,42});
return 0;
}
