public ActionResult Index(double controlVisits,double controlConversions,double testVisits,double testConversions)
        {
            var model = new ConfidenceCalculator(controlVisits, controlConversions);

            model.AddTest(testVisits,testConversions);

            return View(model);
        }
        public void TestZScore(double visited, double converted, double rate, double score)
        {
            var conversions = 35d;// Conversion Rate of control
            var visitors = 182d;// Sample size of control

            var calc = new ConfidenceCalculator(visitors, conversions);

            calc.AddTest(visited, converted);

            ConfidenceRow row = calc.Tests.First();

            Assert.That(row.ZScore,Is.EqualTo(score).Within(0.01));
        }