diff --git a/networks.rkt b/networks.rkt
index 38d72f3..8139303 100644
--- a/networks.rkt
+++ b/networks.rkt
@@ -81,6 +81,7 @@
                [random-boolean-network/vars (number? . -> . network?)]
                [tbf/state-w (-> tbf/state? (hash/c variable? number?))]
                [tbf/state-θ (-> tbf/state? number?)]
+               [make-tbf/state (-> (listof (cons/c variable? number?)) number? tbf/state?)]
                [apply-tbf-to-state (-> tbf? state? (or/c 0 1))])
  ;; Predicates
  (contract-out [variable? (-> any/c boolean?)]
@@ -950,5 +951,9 @@
 (define tbf/state-w tbf/state-weights)
 (define tbf/state-θ tbf/state-threshold)
 
+;;; Makes a state/tbf from a list of pairs of names of variables and
+;;; weights, as well as a threshold.
+(define (make-tbf/state pairs threshold)
+  (tbf/state (make-immutable-hash pairs) threshold))
 ;;; A TBN is a network form mapping TBFs to variables.
 (define tbn? (hash/c variable? tbf?))