M@x,
<!DOCTYPE HTML>
<html>
<head>
<title>Untitled</title>
<meta charset="utf-8">
<script>
function yesChange()
{
var obj = {},select = document.querySelectorAll("[id^='family']"), show = document.querySelector(".show"),str = '' ;
for (var i=0; i<select.length; i++) {
var num = select[i].value;
obj[num] = (obj[num]||0)+1;
};
for(var k in obj) str += k + ' повторяется ' + obj[k] + '<br />'
show.innerHTML = str
}
</script>
</head>
<body>
<select name="" id="family_1_stat">
<option >1</option>
<option >2</option>
<option >3</option>
</select>
<select name="" id="family_2_stat">
<option >1</option>
<option >2</option>
<option >3</option>
</select>
<select name="" id="family_3_stat">
<option >1</option>
<option >2</option>
<option >3</option>
</select>
<select name="" id="family_4_stat">
<option >1</option>
<option >2</option>
<option >3</option>
</select>
<select name="" id="family_5_stat">
<option >1</option>
<option >2</option>
<option >3</option>
</select>
<button id="submit" onclick="yesChange()">submit</button>
<div class="show"></div>
</body>
</html>