1. 고려대학교 산업공학과 IND641 Engineering Psychology Chapter 9. Selection of Action  OVERVIEW  skill-based behavior – the most automated level; a rapid automatic responses with a minimum investment of resources; extensive training and experience  rule-based behavior – action by bringing into WM a hierarchy of rule – less automatic and timely  knowledge-based – entirely new problems; neither rule nor automatic mappings exist – diagnoses, decisions, troubleshooting  selection of skill-based actions – response time or reaction time (RT) – simple and choice RT  VARIABLES INFLUENCING BOTH SIMPLE AND CHOICE REACTION TIME  stimulus Modality  simple RT to auditory stimulus (130 msec) is faster than visual stimuli (170 msec)  Stimulus Intensity  simple RT decreased with increases in intensity of the stimulus to an asymptotic value  aggregation over time of evidence in the sensory channel until a criterion is exceeded  temporal Uncertainty  the degree of predictability of when the stimulus will occur  manipulated by warning interval (WI) between a warning signal and imperative stimulus to which the person must response  short and constant WI  imperative stimulus is highly predictable (temporal uncertainty is low)  short RT  long or variable WI  high temporal uncertainty  long RT

2. 고려대학교 산업공학과 IND641 Engineering Psychology  Expectancy  RT increases as the average WI of a block of trials becomes longer (temporal uncertainty)  an opposite effect is observed within a block having randomly varied long and short WIs – the concept of expectancy  VARIABLES INFLUENCING ONLY CHOICE REACTION TIME  The Information Theory Model: The Hick-Hyman Law  choice RT was longer than simple RT  RT was a negatively accelerating function of the number of stimulus-response alternatives  Hick (1952) and Hyman (1953) applied information theory to quantify the uncertainty of stimulus events  choice RT increased linearly with stimulus information (log 2 N)  RT = a + bH s (Hick-Hyman law)  human has a relatively constant rate of processing info, defined by inverse slope (1/b) (bits/sec)  The Speed-Accuracy Trade-off  they tend to make more errors as they try to respond more rapidly  bandwidth as H t /RT (bits/sec)  constant bandwidth model of human performance is not quite accurate  Howell and Kreidler (1963, 1964) – easy and complex choice RT tasks by different instructions – fast, accurate, fast and accurate, maximize H t  instructions changed RT and error rate; speed instruction having the largest effect  easy choice RT – max. H t obtained by maximize H t instruction  complex choice RT – highest level of performance efficiency with speed set instruction

3. 고려대학교 산업공학과 IND641 Engineering Psychology  The Speed-Accuracy Operating Characteristic (SAOC)  RT is on the x-axis and accuracy (error rate) on the y axis  info. transmission (performance efficiency) is optimal at intermediate speed-accuracy sets  accuracy (=log[P(correct)/P(errors)])  linear SAOC  one important aspect of the speed-accuracy trade-off is its usefulness in deciding what is “best”  The Speed-Accuracy Micro-Trade-off  compare the accuracy of fast and slow responses within a block of trials, using the same system (or experimental condition) – depend on the particular nature of the RT task  when the criterion is conservative  processing full info, taking longer time  high accuracy  when the criterion is risky  response initiated rapidly, based on little evidence  errors will be likely  in the extreme  “fast guess” – a random response initiated as soon as the stimulus is detected  error RTs are faster than correct RTs when RTs are short and stimulus quality is good  if poor stimulus, long processing or working memory load – opposite form of micro-trade-off  error responses tend to be slower than correct ones  DEPARTURE FROM INFORMATION THEORY  Stimulus Discriminability  RT is lengthened as a set of stimuli are made less discriminable from one another  similarity or difference – the ratio of shared features to total features within a stimulus  discriminability difficulty reduced by deleting shared and redundant features where possible

4. 고려대학교 산업공학과 IND641 Engineering Psychology  The Repetition Effect  repetition effect, the advantage of repetitions over alternations, is enhanced by increasing N (the number of S-R alternatives), by decreasing S-R compatibility, and by shortening the interval between each response and the subsequent stimulus  No repetition effect 1.long intervals between stimuli and may be replaced by an alternation effect (faster RT with a stimulus change) – gambler’s fallacy  do not expect a continuous run of the same sort 2.rapid repetition of the same finger slower than alternations  Response Factors 1.RT is lengthened as the confusability between responses is increased 2.RT is lengthened by the complexity of the response  Practice  practice decreases the slope of the Hick-Hyman law function relating RT to info  compatibility and practice appear to trade off reciprocally in their effect on this slope  Executive Control  it takes time to load or activate these rules when they are first used or shift from one to another  the function of central executive control  Stimulus-Response Compatibility  Location Compatibility  provided by human’s intrinsic tendency to move or orient toward the source of stimulation

5. 고려대학교 산업공학과 IND641 Engineering Psychology  colocation principle – controls next to the relevant display – not always possible to achieve  congruence – congruence between spatial controls and displays; often defined in terms of an ordered array rule  increase from left to right, aft to forward, clockwise, bottom to top  far-right to top when left-right array mapped to a vertical display  top-down ordering is not strong  vertical display (or control) arrays that are not congruent with control (display) arrays should be used with caution  put a slight cant, or angling, of one array in a direction that is congruent with the other  Movement Compatibility  the set of expectancies that an operator has about how the display will respond to the control activity: Cognitive-Response-Stimulus (C-R-S) compatibility  congruence principle of location compatibility applied to the compatibility of movement  when congruence violated, a common mapping of increase  also governed by a principle of movement proximity (Warrick principle) -- not related to congruence  Compatibility Ambiguities  mental model 1.movement proximity principle was far less pronounced for psychology students than ME students, ME having the strong mental model of the mechanical linkage 2.a design for the vertical speed of an aircraft 3.frame or reference -- exocentric viewpoint (compatible S-R movement), egocentric viewpoint 4.distinction between status and command displays

6. 고려대학교 산업공학과 IND641 Engineering Psychology  Transformations and Population Stereotypes  any S-R mapping that requires some transformation will be reduced in its compatibility  population stereotypes define mappings that are more directly related to experience  Consistency and Training  be wary of possible violation of consistency to optimize the compatibility of each  training can also be used to formulate correct mental model and enhance the agreement between the mental model and the correct dynamics  Knowledge in the World  should provide an invitation to the appropriate actions (affordance) or forcing function, as well as a “lockout” of the inappropriate actions  STAGES IN REACTION TIME  The Subtractive Method  delete a mental operation entirely form the RT task – the decrease in RT is assumed to reflect the time required to perform the absent operation  Additive Factors Technique  confirming evidence for the existence and identity of processing stages  to define the existence and distinctiveness of different stages by manipulating variables that are known to lengthen reaction time  interactive (influence a common stage of processing); additive (influence different stages)  Experimental Techniques  make inferences about what manipulations influence what stages of processing  patterns of additivity and interactions (fig 9.12)

7. 고려대학교 산업공학과 IND641 Engineering Psychology 1.the response selection is a major bottleneck in speeded information processing 2.stimulus probability appears to affect two stages 1.improbable stimuli require longer to be recognized 2.their associated responses take longer to be selected  Applications of Additive Factors Methodology  how information processing speed is influenced by aging, poisoning, mental workload  Problems With Additive Factors  the assumption that stages proceed strictly in series  convincing evidence that information processing does not strictly proceed in a serial fashion  underadditive relationship – delay by increasing the difficulty at one stage of processing is actually smaller at the more difficult level of the other stage  The Event-Related Brain Potential as an Index of Mental Chronometry  event-related brain potential (ERP)  a direct estimate of the timing of processes up to the intermediate stage of stimulus categorization – a series of electric voltage from the surface of the scalp  The Value of Stages  the separation of processing stages should not taken too literally  some overlap in time between processing in successive stages – parallel processing  the stage concept more than compensates for any limitations in its complete accuracy  SERIAL RESPONSES  The Psychological Refractory Period  PRP – a situation in which two RT tasks are presented close together in time

8. 고려대학교 산업공학과 IND641 Engineering Psychology  ISI (interstimulus interval) – the separation in time between the two stimuli – SOA  the second stimulus response is delayed by the processing of the first under short ISI  human being as a single-channel processor of information  the processing of S 1 temporarily captures the single-channel bottleneck  S 2 must wait until S 1 is finished  anything that prolongs the processing of S 1 will increase the PRP delay of RT 2 (simple reaction vs. choice reaction)  perceptual analysis of S 2 can proceed even as the processor is fully occupied  the delay in RT 2 will increase linearly with a decrease in ISI and with an increase in the complexity of RT 1 (fig. 9.15)  general single-channel model 1.with short ISI (< 100 ms), both responses are emitted together (grouping) and both are delayed 2.sometimes RT 2 suffers a PRP delay even when the ISI is greater than RT 1  feedback  The Decision Complexity Advantage  the most restricting limit in human performance relates to the absolute # of decisions/sec rather than the # of bits/sec (cf. bandwidth) – the frequency of decisions and their complexity do not trade off reciprocally  decision complexity advantage  some fundamental limit to the central-processing or decision-making rate, independent of decision complexity, that limits the speed of other stages of processing – 2.5 decisions/sec for decisions of the simplest possible kind  Pacing  the circumstances under which the operator proceeds from one stimulus to the next

9. 고려대학교 산업공학과 IND641 Engineering Psychology  dichotomous dimension  force-paced schedule – constant interval, ISI, independent of the operator’s response  self-paced schedule – response-stimulus interval (RSI), depend on the latency of the operator’s response  continuous dimension – defines the value of the timing parameters (RSI, ISI)  Response Factors  Response Complexity  increased complexity requires more monitoring of the response -- sometimes delay  Response Feedback  two effects on performance, depending on the sensory modality 1.delays, distortions, or elimination of the intrinsic feedback (the perceived sound of one’s voice or the visualization of one’s moving hand) – substantial deficits in performance 2.less serious distortion of extrinsic feedback (the click of a depressed key or the appearance of a visual letter on a screen – delay or distortion of feedback can be harmful  Response Repetition  response is slowed by its repetition  single trial RT paradigm (repetition is good)  eliminates the repeated engagement of the response selection stage – time saved  reaction time relatively long (200 – 300 msec) compared to typing  typing -- response is slowed by its repetition  high speed in typing  separate responses selected without engaging a higher-level decision process  no longer any benefit to repetitions by bypassing  advantageous to employ separate muscle groups for successive responses (advantage for alternation)

10. 고려대학교 산업공학과 IND641 Engineering Psychology  Preview and Transcription  the class of transcription tasks (e.g., typing, reading aloud, and musical sight reading) allow the operator to make use of preview, lag, and parallel processing  more than one stimulus displayed at a time (preview is available)  lag the response behind perception  perception and response are occurring in parallel  preview (seeing into the future) or lag (responding behind the present)  possible in self-paced (typing) or force paced (oral translation) tasks  maintain a running “buffer” memory of encoded stimuli that have not yet been executed as responses  benefits of lag 1.allowance for variability 2.allowance for chunking  Allowance for Variability  a steady stream of output at a constant rate can proceed even if input encoding is temporarily slowed  Allowance for Chunking  evidence in typing that inputs are encoded in chunks  letters in each chunk processed more or less in parallel  the output must be serial  encoding, buffer storage, response – proceed in parallel with little mutual interference, and are even time shared with a fourth mental activity, the monitoring of errors in response

11. 고려대학교 산업공학과 IND641 Engineering Psychology  Use of Preview  preview helps performance  benefits of preview  making available more advance information  giving the operator an opportunity to perceive chunks  not related to the semantic level of processing but chunk-sized units to be processed in parallel  the benefits of chunking are primarily perceptual and may be seen in storage but not in response