I am stuck! Why in the world does this calculate the estimated(population) variance rather than the actual variance:
Any help would be appreciated. I use this function to calculate the standard deviation.
double calculateVariance(StudentsGrades obj, double meanAvg)
for(int index = 0; index < MAX_NUM_STUDENTS; index++)
if((obj[index].getStudentAvg() == 0) || (obj[index].getStudentAvg() == meanAvg))
variance += 0.0;
else variance += pow(obj[index].getStudentAvg() - meanAvg, 2);
variance = variance / TOTAL_STUDENTS; // TOTAL_STUDENTS is one less than
// MAX_NUM_STUDENTS because
// the data file has titles for each column
I have googled every where and can't find the solution and I have used a calculator and
MS Excel to check the numbers, and they are off.