Fix & update for calc-confidence

* The local `stop?` variable in the calc-confidence procedure caused unintended consequences in conjunction with `g-depressed-confidence`. It sometimes lead to researchers not properly updating their `avg-neighbor-signal`. Therefore the `stop?` variable has been removed.
* In case of de-facto complete networks the calculation of `avg-neighbor-signal` can be simplified. This has been implemented.
* The condition for when an update from nature is happening has been fixed inside the `calc-confidence` procedure.

protocol.nls

@@ -33,8 +33,8 @@ end
 
 
 
-; reports true if all scientists converged to one theory and consider this theory
-; to be among their best theories
+; reports true if all scientists converged to one theory and consider this 
+; theory to be among their best theories
 to-report converged
   let count-th1-scientists count turtles with [
     mytheory = 0 and member? 0 cur-best-th]  
@@ -80,35 +80,48 @@ end
 ; change her mind). This calculation only makes sense in case researchers have
 ; converged.
 to calc-confidence
-  if converged-ticks = 0 [
+  ;force-update is a boolean. It is true if scientists just converged this round
+  let force-update? (converged-ticks = 0)
+  if force-update? [
     set g-depressed-confidence false
   ]
   if g-depressed-confidence [stop]
-  let stop? false
+  let force-nature-update? 0
+  if not force-update? [
+    ; the -1 correction in ticks compensates for the fact that this procedure
+    ; will be called after the go procedure and therefore the tick-counter has 
+    ; already advanced one step further
+    set force-nature-update? (nature-evidence-frequency > 0 
+      and ticks > 1 
+      and (ticks - 1) mod (1 / nature-evidence-frequency) = 0)
+  ]
+  let cur-theory [mytheory] of one-of turtles
+  let other-theory ((cur-theory + 1) mod 2)
+  let avg-neighbor-signal-complete 0
+  if g-fast-sharing-enabled and (force-update? or force-nature-update?) [
+    set avg-neighbor-signal-complete mean [item cur-theory subj-th-i-signal] of 
+        turtles
+  ]
   ask turtles [
-    if stop? and nature-evidence-frequency = 0 [stop]
-    let belief-to-beat item ((mytheory + 1) mod 2) current-theory-info
+    let belief-to-beat item other-theory current-theory-info
       - strategy-threshold
     ; not entirerly sure whether this cutoff at 0 is needed, but I've added it 
     ; for cautionarly reasons
-    set belief-to-beat max (list 0 belief-to-beat)
-    let cur-theory mytheory
-    ; the -1 correction in ticks compensates for the fact that this procedure
-    ; will be called after the go procedure and therefore the tick-counter has 
-    ; already advanced one step further
-    if converged-ticks = 0 or (nature-evidence-frequency > 0 
-      and (ticks - 1) != 0 
-      and (ticks - 1) mod (1 / nature-evidence-frequency) = 0) [
-      set avg-neighbor-signal mean [item cur-theory subj-th-i-signal] of 
-        (turtle-set link-neighbors self)
+    set belief-to-beat max (list 0 belief-to-beat)    
+    if force-update? or force-nature-update? [
+      ifelse g-fast-sharing-enabled [
+        set avg-neighbor-signal avg-neighbor-signal-complete
+      ][
+        set avg-neighbor-signal mean [item cur-theory subj-th-i-signal] of 
+          share-group
+      ]
     ]
     ; if the scientist would be given sufficient time for her belief to
     ; converge to the average signal of her and her link-neighbors, would
     ; this be enough for her to abandon her current theory? If so, she's not
     ; confident enough.
     if avg-neighbor-signal <= belief-to-beat [
       set confidence 0
-      set stop? true
       set g-depressed-confidence true
       stop
     ]
@@ -119,7 +132,6 @@ to calc-confidence
     let delta item mytheory current-theory-info - belief-to-beat
     if (2 * alpha - 1) * delta <= belief-to-beat [
       set confidence 0
-      set stop? true
       stop
     ]
     let exit-probability 0.5 + 0.5 * erf (
@@ -134,11 +146,7 @@ to calc-confidence
      set confidence 1
     ]
   ]
-  ifelse stop? [
-    set g-confidence 0
-  ][
-    set g-confidence reduce * [confidence] of turtles
-  ]
+  set g-confidence reduce * [confidence] of turtles
 end