how to filter using multiple check box value from mysql database using jquey and php

I have a dynamic page ie. all-offer.php?category=beauty-spa according to category i have some stores to display and respective all location with checkbox according to category. html part according to category

<?php 
                    foreach($qry_1 as $v){
                    ?>
                        <a class="col-md-4" href="#">
                            <div class="product-thumb">
                                <header class="product-header">
                                    <img src="<?php echo str_replace('../','',$v['offer_image']) ?>" alt="Image Alternative text" title="Ana 29" />
                                </header>
                                <div class="product-inner">
                                    <h5 class="product-title"><?php $v['title'] ?></h5>
                                    <p class="product-desciption"><?php $v['description'] ?></p>

                                    <p class="product-location"><i class="fa fa-map-marker"></i> <?php echo $v['location'] ?></p>
                                </div>
                            </div>
                        </a>
                        <?php
                    }
                        ?>

from above code i can able to fetch all outlets and their locations i want to filter outlets if i checked the location checkbox. i get the checkbox value using jquey and post it to filter.php

$('input#locality').change(function () {
  var locality = [];
  $(':checkbox:checked').each(function (i) {
    locality.push($(this).val());
});
$.ajax({
            type:'POST',
            url:"php/filter.php",
            data:{name: locality},
            dataType:"json",
            success: function(data){
                $.each(data, function(index, element) {

                    $('.response').append('')

                });
                }})
});

and i received the data in filter.php part is

$qry_1=array();

    $checkbox1=$_POST['name'];  
$chk="";   
foreach($checkbox1 as $chk1)  
   {  
      $chk .= $chk1;  
   }
$sql_1="SELECT  p.id,p.outlet_id,p.offer_title,p.original_price,p.discount,p.discount_price,p.offer_image,p.offer_details,o.outlet_id,o.outlet_title,o.outlet_locality,o.segment_type FROM products as p,outlets as o WHERE p.outlet_id=o.outlet_id AND o.outlet_locality='$chk'"; 
$qry_1=sel_qry($sql_1);
foreach($qry_1 as $v)
{
    $filterloc[]=array('title'=>$v['outlet_title'],'cat_id'=>$v['outlet_id']);
}
echo json_encode($filterloc);  

i m getting error when i check multiple checkbox it shows $filterloc is not defined my question is how to get data as json in jquery and refresh my content according to location checked