<input type="hidden" id="position" value="<?php echo $this->session->userdata('position') ?>">   <--hidden element to store position
$(document).ready(function()
    {
        var position = $('#position').val();
        if(position=="Finance"){
            $('#limasterdata').remove();          <-- ('#limasterdata') is your sidebar <li> element
        }
        else if(position=="HRD"){
            $('#litransaction').remove();
        }
        else if(position=="Administrator"){
            alert('Welcome Admin!');
        }
    });