p446fig12.44 (left column, top row) LIST PARSE can model linguistic data from human subjects.  In this figure, model parameters are fixed to enable a close fit to data about error-type distributions in immediate free recall experiments, notably transposition errors.  (right column, top row) Simulation and data showing bowing of the serial position curve, including an extended primacy gradient.  (left column, bottom row) The simulation curve overlays data about list length effects, notably the increasing recall difficulty of longer lists during immediate serial recall (ISR).  (right column, bottom row) Simulation (bottom image) and data (top image) of the limited temporal extent for recall.<BR>||  (1. TL) Error-type distributions in immediate serial recall (Hanson etal 1996). % occurence vs serial position.  Graph convention: Data- dashed lines; Simulations- solid lines.  Six letter visual ISR.  Order errors- transpositions of neighboring items are the most common.  Model explanation: Noisy activation levels change relative oorder in primacy gradient.  Similar activation of neighboring items most susceptible to noise.  Model paramenters fitted on these data.<BR>(2. TR) Bowing of serial position curve (Cowan etal 1999). % correct vs serial position.  Auditory ISR with various list lengths (graphs shifted rightward): For [, sub-]span lists- extended primacy, with one (or two) item recency;  Auditory presentation- enhanced performance for last items.  LIST PARSE:  End effects- first and last items half as many members;  Echoic memory- last presented item retained in separate store.<BR>(3. BL) List length effects, circles (Crannell, Parrish 1968), squares (Baddeley, Hitch 1975), solid line- simulation.  % list correct vs list length.  Variable list length ISR:  longer lists are more difficult to recall.  LIST PARSE:  More items- closer activation levels and lower absolute activity level with enough inputs;  Noise is more likely to produce order errors, Activity levels more likely to drop below threshold;.<BR>(4. BR) Limited temporal extent for recall (Murdoch 1961).  % recalled vs retention interval (s).  ISR task with distractor-filled retention intervals (to prevent rehersal): Increasing retention interval - decreases probabilty of recalling list correctly;  Load dependence- longer list more affected by delays; Performance plateau- subjects reach apparent asymptote.  LIST PARSE: Increase convergence of activities with time; loss of order information;.