1 / 13

Week 10-1: Selection of Action

Week 10-1: Selection of Action. Week 10 Topics. Lecture 10-1 Types of Actions Simple Reaction Time Choice Reaction Time Hick-Hyman Law Lecture 10-2 Speed-Accuracy trade-offs Variables affecting Choice RT. Selection of Action. Types of actions (Rasmussen, 1980, 1986)

Download Presentation

Week 10-1: Selection of Action

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.


Presentation Transcript

  1. Week 10-1: Selection of Action

  2. Week 10 Topics • Lecture 10-1 • Types of Actions • Simple Reaction Time • Choice Reaction Time • Hick-Hyman Law • Lecture 10-2 • Speed-Accuracy trade-offs • Variables affecting Choice RT

  3. Selection of Action • Types of actions (Rasmussen, 1980, 1986) • Skill-based: execution of highly-learned procedural memory—occurs largely outside of awareness • Rule-based: execution of simple “if-then” rules—imposes some working memory load • Knowledge-based: execution of actions based on extensive review of information in the environment and long-term memory – classical decision making

  4. X RT Time Modeling Simple Reaction Time Effects • Criterion model • Two parameters • Aggregation rate of the stimulus (bottom-up) • Criterion set (top-down) • Action taken when criterion amount of aggregation reached • Effect of Stimulus Intensity • Sensory evidence aggregated (integrated) over time • Stimulus intensity affects rate of information aggregation

  5. X RT Time Variables Influencing Simple Reaction Time • Temporal Uncertainty • warning signals mayprecede imperative stimulus • Warning Interval (WI): interval between warning signal and imperative stimulus • Lowers criterion (top-down effect) • Example: amber traffic light

  6. Variables Influencing Simple Reaction Time • Effect of Variations in Warning Interval (WI): • WI short and constant (e.g., 0.5 s) • Temporal uncertainty reduced or eliminated • RTs shorten to nearly 0 • WI long or variable • Temporal uncertainty is increased • Uncertainty in internal timing mechanism increases linearly with duration • Simple RTs increase, reach maximum of 700ms

  7. Variables Influencing Simple Reaction Time • Expectancy • Modeled as a criterion shift • Faster RTs • more false alarms • If WI is varied within a block, expectancy increases for longer WIs • EXAMPLE: Van Der Horst (1988) Vehicle controlled traffic lights • Driver expects the light to remain green since he knows the light senses his vehicle • RT to yellow light is delayed by a second!

  8. Variables Influencing Choice Reaction Time • Amount of information transmitted is important • Choice RT requires operator to map stimulus to response -- information must be transmitted • More complex decisions (requiring more information) require longer to initiate • Information Theory: Three variables influence information conveyed by a stimulus • Number of possible stimuli • Probability of a stimulus • Context or sequential constraints

  9. Information & Choice Reaction Time • Hick-Hyman Law • Choice RT increases linearly with magnitude of stimulus information • Hyman (1953) also varied the probability and sequential expectancy (context) of a stimulus • Information theory: unequal probabilities reduce the average amount of stimulus information • Mean RT for block of trials is shortened by this reduction of information accordingly, thus

  10. Stimulus Frequency & Choice Reaction Time • Fitts, Peterson, and Wolpe (1963) • Examined RT to highly frequent and rare events • Prediction of Hick-Hyman • frequent events have little information, rare events have high information • fast RT for frequent events, slow RT for rare events • IMPORTANT IMPLICATION! • RT for real world tends to take much longer than in lab studies • Summala (1981) Time to break in response to a roadway obstacle is estimated to be 2-4 seconds • Why?

  11. Accuracy and Choice Reaction Time • Speed-accuracy trade-off • Tendency to make more errors as you try to respond faster • Hick-Hyman: constant bandwidth for information transmission • Constant bandwidth mean that if speeded response doesn’t allow for all information to be transmitted, then not enough information will be transmitted for accurate responses • Human performance does not exactly follow the constant bandwidth assumption

  12. Speed-Accuracy Operating Characteristic • SAOC curve • Similar to P(H) & P(FA) in SDT • Analogous to the ROC curve in SDT • Bias toward speed or accuracy is analogous to bias in SDT toward increasing hits or reducing FA accuracy stress Good (fast & accurate) log[P(correct)/P(error)] Poor (slow & sloppy) speed stress RT

  13. System design and the Speed-accuracy Tradeoff • Certain design features seem to automatically shift performance along the SAOC • Auditory presentation enhances speed emphasis • Aircraft designers use auditory displays only for critical alerts that require quick responses • Presentation of more information will tend to slow performance and increase accuracy • Older adults tend to have an accuracy-emphasis • Stress can induce a speed emphasis • Some nuclear power regulations require operator to take no action for a period of time after a fault

More Related