Java Utililty Methods ArrayList Average

double avg = 0.0;
for (int i = 0; i < nums.size(); i++) {
    avg += nums.get(i);
return avg / (double) nums.size();

Integer sum = 0;
if (!array.isEmpty()) {
    for (Integer mark : array) {
        sum += mark;
    return sum.doubleValue() / array.size();
return sum;
...

ArrayList<ArrayList<String>> valuesInColumns = valuesInColumns(lines);
ArrayList<String> result = new ArrayList<String>();
for (int i = 0; i < valuesInColumns.size(); i++) {
    ArrayList<String> values = valuesInColumns.get(i);
    Double sum = 0.0;
    for (String value : values) {
        try {
            sum = sum + Double.parseDouble(value);
...

Small routines doing trivial stuff here

double ave = 0;
int i, size = data.size();
for (i = 0; i < size; i++) {
    ave += ((Double) data.get(i)).doubleValue();
ave /= (double) size;
return ave;

double sum = 0;
for (double value : values) {
    sum += value;
return sum / values.size();

int amountOutliers = 0;
double addedUp = 0;
for (int index = 0; index < values.size(); index++) {
    if (isOutlier(index, values)) {
        amountOutliers++;
        addedUp += values.get(index);
return addedUp / (values.size() - amountOutliers);