Edit in JSFiddle

<label>
    <input name="aspnet" type="radio" value="webforms" data-bind="checked: technique" />ASP.NET Web Forms
</label>
<label>
    <input name="aspnet" type="radio" value="mvc" data-bind="checked: technique" />ASP.NET MVC
</label>
<label>
    <input name="aspnet" type="radio" value="webapi" data-bind="checked: technique" />ASP.NET Web API
</label>
<div data-bind="text: techniqueText"></div>
function ViewModel() {
    var self = this;
    self.technique = ko.observable("");
    self.technique.subscribe(function (newValue) {
        self.techniqueText($("input[name=aspnet]:checked").parent().contents().filter(function () {
            return this.nodeType == 3;
        }).text());
    });
    self.techniqueText = ko.observable("");
}

ko.applyBindings(new ViewModel());