diff --git a/R/server.R b/R/server.R
index 5d906a1..55acf1c 100644
--- a/R/server.R
+++ b/R/server.R
@@ -2,11 +2,15 @@
 #' @noRd
 server <- function(input, output, session) {
   ranked_data <- reactive({
-    total_weight <- abs(input$cross_sample_weight) + abs(input$sd_expression)
+    total_weight <- abs(input$cross_sample_weight) +
+      abs(input$mean_expression) +
+      abs(input$sd_expression)
+
     data <- data.table::copy(ubigen::genes)
 
     data[, score :=
       (input$cross_sample_weight * get(input$cross_sample_metric) +
+        input$mean_expression * mean_expression_normalized +
         input$sd_expression * sd_expression_normalized) /
         total_weight]
 
diff --git a/R/ui.R b/R/ui.R
index 0294337..56bb791 100644
--- a/R/ui.R
+++ b/R/ui.R
@@ -41,6 +41,17 @@ ui <- function() {
             step = 0.01,
             value = 0.5
           ),
+          sliderInput(
+            "mean_expression",
+            verticalLayout(
+              strong("Mean Expression"),
+              "Mean expression of the gene across all samples."
+            ),
+            min = -1.0,
+            max = 1.0,
+            step = 0.01,
+            value = 0.25
+          ),
           sliderInput(
             "sd_expression",
             verticalLayout(
@@ -50,7 +61,7 @@ ui <- function() {
             min = -1.0,
             max = 1.0,
             step = 0.01,
-            value = -0.5
+            value = -0.25
           )
         ),
         mainPanel(