在本教程中,我们将讨论实现均值标准误差的程序。
平均值的标准误是根据总体平均值估算样本平均值的离散度。然后用于估计平均值的近似置信区间。
#include <bits/stdc++.h>
using namespace std;
//calculating sample mean
float calc_mean(float arr[], int n){
float sum = 0;
for (int i = 0; i < n; i++)
sum = sum + arr[i];
return sum / n;
}
//calculating standard deviation
float calc_deviation(float arr[], int n){
float sum = 0;
for (int i = 0; i < n; i++)
sum = sum + (arr[i] - calc_mean(arr, n)) * (arr[i] - calc_mean(arr, n));
return sqrt(sum / (n - 1));
}
//calculating sample error
float calc_error(float arr[], int n){
return calc_deviation(arr, n) / sqrt(n);
}
int main(){
float arr[] = { 78.53, 79.62, 80.25, 81.05, 83.21, 83.46 };
int n = sizeof(arr) / sizeof(arr[0]);
cout << calc_error(arr, n) << endl;
return 0;
}输出结果
0.8063