My Problem Is Msterpage Refresh Every Time I Click The Type Control In Asp.Net

<div class="col-sm-9 col-sm-offset-3 col-md-10 col-md-offset-2 main">
<div class="row margintop">
<div class="col-md-12">
<ul class="nav nav-tabs" id="myTab">
<li id="nielsenclick" class="active">Jan</li>
<li id="secclick">Feb</li>
<li>Mar</li>
<li >Appr</li>
</ul>
</div>
<div class="col-md-12">
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">

</div>
</div>
</div>

-----// Js //-----

$('#myTab a').click(function (e) {
e.preventDefault()
$(this).tab('show')
debugger;
var name = $(this).text();
if (name == 'Jan') {
$('#Label1').html(name);
$('#nielsenclick').addClass('active');
window.location.href = "Nielsen.aspx";
}
if (name == 'Feb') {
window.location.href = "Sec_Single_Metric_Charts.aspx";
$('#secclick').addClass('active');
}
})

Here Default Menu active is jan but i select Feb It is not Active state master page is refreshed