jquery validate

<!DOCTYPE html>
<html lang="es-419">
    <head>
        <meta charset="utf-8">
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <title>Registro de Alumnos</title>
        <link href="http://maxcdn.bootstrapcdn.com/bootswatch/3.3.4/simplex/bootstrap.min.css" rel="stylesheet">

    </head>
    <body>

        <div class="container">

        <form id="form" role="form">

            <h1 class="a-title">Registro de Alumnos </h1>

            <div class="form-control">
                 <input type="text" name="name" id="name" form="form" data-required="true" data-pattern="^[a-z]+$" data-describedby="name-description" data-description="name" />
                 <label for="name" class="add-on"><span class="icon-asterisk"></span>Name</label> <br><br><br>
            </div>

            <div id="name-description">
                 <!-- -->
            </div>

            <hr>

            <span id="messages"></span>

            <button type="submit" id="btnEnviar" value="Enviar" class="btn btn-default submit-buttom">Enviar Formulario</button>

            <button type="reset" class="btn btn-default submit-buttom">Blanquear formulario</button>

        </form>

        </div>

        <!-- scripts -->

        <script src="js/vendor/jquery-1.9.0.min.js"></script>
        <script src="js/jquery-validate.min.js"></script>


        <script>


                 $('#form').validate({
                         onKeyup : true,
                            sendForm : true,
                            eachValidField : function() {
                                $(this).closest('div').removeClass('error').addClass('success');
                            },
                            eachInvalidField : function() {
                                $(this).closest('div').removeClass('success').addClass('error');
                        },
                        rules: {
                            name: { required: true, minlength: 2 }
                        },
                        messages: {
                            name: "Debe introducir su nombre."
                        },
                        description : {
                                name : {
                                    required : '<div class="alert alert-danger">Required</div>',
                                    pattern : '<div class="alert alert-danger">Pattern</div>',
                                    conditional : '<div class="alert alert-danger">Conditional</div>',
                                    valid : '<div class="alert alert-success">Valid</div>'
                                }
                            }
                    });


     </script>

    </body>
</html>