u¶
Note: Applicable in all mechanisms except the Rescorla-Wagner mechanism. (In the Rescorla-Wagner mechanism, use lambda to specify reinforcement values.)
Specifies the reinforcement values for stimulus elements, used when updating v-values. See The mechanisms.
The parameter u
can be set to certain values for certain particular stimulus elements.
It can also be specified as a single value, in which case the same reinforcement value is used for all
stimulus elements.
Syntax¶
u = e1: v1, e2: v2, ..., en: vn, default: d
u = v1
where v1,v2,...,vn
are scalar expressions.
Description¶
u = e1: v1, e2: v2, ..., en->bn: vn, default: d
sets the reinforement value for
e1 to v1,
e2 to v2, …,
en to vn,
and the reinforcement value for all other stimulus elements to d.
The specification is independent of the list order:
u = e1:v1, e2:v2, default:d
is the same as
u = e2:v2, default:d, e1:v1
.default
need not be specified if all stimulus elements are present in the list. For example,stimulus_elements = e1, e2 u = e1:v1, e2:v2
u = v1
sets the reinforcement value for all stimulus elements to v1.
u = v1
is the same asu = default: v1
.
Dependencies¶
The property
stimulus_elements
must be specified beforeu
.Each stimulus element used in the specification of
u
must be present in the parameterstimulus_elements
.Not applicable in the Rescorla-Wagner mechanism.
Examples¶
@variables x = 1
u = element1: x, element2: x+1, default:x+2
sets the reinforcement value for element1 to 1 and for element2 to 2, and for the remaining stimulus elements to 3.
u = element1: 0.5, default:0
sets the reinforcement value for element1 to 0.5, and for the remaining stimulus elements to 3.
u = 0.1
sets the reinforcement value for all stimulus elements to 0.1.