Information vs Knowledge Flashcards
working memory
handles relatively short-term (but volatile) storage and processing of memories- duration may be unlimited–as long as memory is actively rehearsed; is prone to interference- can hold 7 ± 2 items- codes information phonologically, visually, or semantically
working memory and implications for design
• minimize “cognitive load”: reduce number of things people are required to remember• provide visual “echoes”e.g., automated 411 services that speak a number could use phone’s display as well• provide placeholders for sequential tasks• exploit “chunking”: strategy that organizes several memory items into a larger whole - physical chunk size: optimal size is 3-4 numbers or letters per chunk- meaningful sequences:e.g., 7, 8, and 0 represent one chunk - letters superior to numbers:e.g., 1-800-GET-HELP- keep numbers separate from letters:e.g., licence plate of “458 GTS” better than “4G5 8TS”• minimize confusabilitye.g., A5433 easily confused with A5423; sound-alike letters confused with each other:B C P T and V• avoid unnecessary zerose.g., 002385 takes up unnecessary memory• ordering of text and instructionse.g., poor design: “before doing B, do A first” e.g., good design: “do A, then do B”• minimize distractions/interruptionse.g., compared to rotary phones, touch tone phones allow faster dialing, reducing riskof interruptions
long-term storage
handles longer-term, more stable memories; potentially unlimited capacity and duration• declarative (or explicit) memory: “knowing what”- episodic memory: specific, “autobiographical” events - semantic memory: facts, general knowledge• procedural (or implicit) memory: “know-how”
long-term memory/storage and implications for design
• encourage regular use of information- memory traces are strengthened by frequency and recency e.g., practice effects• standardizee.g., shift pattern for manual transmission is becoming standardized; same commandworks in different Windows® programs carefully design information to be remembered- should be meaningful/semantically related to other knowledge- avoid arbitrary memory, which makes it difficult to learn, and recover from errors:e.g., all prime ministers, Alt-F4 in Windows® - use concrete, not abstract words- distinctiveness reduces interference- organization/grouping- avoid jargonuse memory aids!-prompt user for correct operational sequencedesign to support correct mental models, using natural designknow that memory is not necessarily precise or infallible, is reconstructive!-introduced $1 coin to US, people confused with quarter, CHAOS ENSUES
the seven sins of memory
Sins of Omission/Forgetting1. Transience2. Absent-Mindedness3. BlockingSins of Commission/Distortion4. Misattribution5. Suggestability6. Bias7. Persistence
Sins of Omission/Forgetting: transience
memory for facts and events becomes less accessible over time, both in short-term and long-term memory e.g., forgetting a phone number- causes: interference, retrieval failureGOOD it may be useful to forget old/outdated knowledge BAD but we may lose some that we need later
Sins of Omission/Forgetting: absent-mindedness
forgetting caused by lapses of attention during encoding or attempted retrievale.g., watching The Amazing Race and burning the cookies- causes: low arousal/fatigue, interruptions/distractions, absence of cuesGOOD directing attention allows selective encoding of informationBAD but attention may be misdirected, precluding encoding
Sins of Omission/Forgetting: blocking
temporary inaccessibility of well-encoded material e.g., tip-of-the-tongue phenomenon- causes: interference from similar itemsGOOD most memory contents should be inhibited or suppressedBAD recall should be of exact item, not similar one(good: Good, because when you are retrying to remember something, you don’t want a flood of a thousand related things that might be it, like a google search. You want THE answer.)
Sins of commission/distortions: misattribution
memory is retained, but an error is made in attributing the sourcea) source confusion: correctly remembering an item or fact, but misattributing it to an incorrect sourcee.g., thinking your friend told you about a great new restaurant, but you actually read about it in the newspaperb) cryptomnesia: misattributing an idea as one’s own, when it is really the product of previous experiences (STEVE JOBS SIGH)e.g., unintentional plagiarismc) false recall/recognition: false remembering of items or events that never happened e.g., thinking you got lost in the mall as a child- causes: reliance on semantic content (gist, not verbatim)(Memory is tied to meaning, not like a tape recorder. Evolutionarily, meaning tends to be the important thing)GOOD content can be encoded wellBAD but at the expense of (often irrelevant) source information
Sins of commission/distortions: suggestability
tendency to incorporate (possibly incorrect) information provided by others into one’s memoriese.g., misleading questions asked of eyewitnesses- causes: memory is constructive, not reproductiveGOOD knowledge structures are changeableBAD plausible information may be incorporated into memory
Sins of commission/distortions: bias
current knowledge, beliefs, and expectations can influence and distort memories; memories of the past may be coloured by present mood/emotional statee.g., remembering bad behaviours of members of a disliked group, more than goodbehaviours- causes: schemas aid interpretation of incoming informationGOOD existing schemas are efficient, and organize knowledgeBAD at the expense of accuracy, when it comes to exceptions
7th sin of memory, intrusive recollections that are difficult to forget: persistence
emembering a fact or event that one would prefer to forgete.g., recollection of traumatic events, chronic phobias- causes: amygdala (limbic system) and stress hormones tied to memory systemGOOD strongly emotional experiences are usually important to remember BAD no way to retain the knowledge without the memory PTSD :(
two types of memory aids
• Signal: don’t forget to remember! e.g., watch alarm, string on fingerGOOD cues rememberingBAD lacks content• Message: content; the info itselfe.g., shopping listGOOD provides contentBAD does not cue remembering- Is this a dichotomy? Is there any other possibility with no cons?- Natural Mappings need no extra reminders or labels; require no extra memory demandor interpretations of signs
tradeoff between knowledge and infomation
(a) knowledge: you know what to doGOOD no external cues neededBAD time/effort is required to gain knowledge (learning) BAD memories are fallible(b) information: you follow instructions no memory demandGOOD external info may be more difficult to BAD use/understandBAD info may disappear (lost manuals)s there any other possibility with no cons?YES, cell phones
Cockpit Checklist: origins
Army getting submissions for new aircraft (1935)-Boeing submitted the favorite, but after test flight, crashed and killed two crew members, injured 3!-cause was “pilot error,” forgot to disengage gust lock-Boeing lost contract, but 12 more aircraft purchased for further testing-pilots decided to make sure nothing would be overlooked again, and developed FOUR checklists: takeoff, flight, before landing, after landing-the 12 aircraft flew 1.8 million miles without a serious accident-army accepted aircraft in 1939, given the designation B-17, THE FLYING FORTRESS!
recent cockpit checklist related crashes
Northwest Airlines flight 255- MD-82 aircraft crashed after takeoff from Detroit in 1987- flight crew failed to ensure flaps and slats configured for takeoff - flight crew distracted by weather and runway change- takeoff warning system had no power (disabled)Delta Air Lines flight 1141- B-727 aircraft crashed after takeoff from Dallas-Fort Worth in 1988- flight crew failed to ensure flaps and slats configured for takeoff- flight crew and flight attendants were discussing dating habits (despite FAA “sterilecockpit” regulation)- takeoff warning horn not operativeUSAir flight 5050-B737 crashed on takeoff, 1989-rudder incorrectly set, takeoff aborted, entered bowery bayALL AVOIDABLE IF CHECKLISTS WERE FOLLOWED
US Federal Aviation Regulation about checklists
a) airlines must have checklist for each aircraft typeb) all items necessary for engines/takeoff/landing/emergencies, designed so people dont need to rely on memoryc) checklist procedure must be “readily usable”checklists for:-proper aircraft configuration (not an option!)-for psychological reasons like team building and to facilitate communication-should NOT be considered a nuisance
Checklist procedure types
-“Do List” follow checklist like recipe (no redundancy)-Challenge-Response: configure aircraft from memory then use checklist as a backup (most common)
engineering vs human factors POV in checklists. tradeoff?
the ITEM!-engineering POV, check EVERYTHING. human factors POV, check critical systems!-tradeoff was the glass cockpit
the glass cockpit
flight deck computers- automated monitoring of flight status- 6 displays: 2 in front of each pilot (flight info), 2 centre console (engine, systemsdata)Degani, Chappell, & Hayes (1991):- analyzed ASRS reports of altitude deviations- crews in glass cockpits detected more deviationsGOOD reduces workloadGOOD more reliableGOOD faster checklist; fewer chances for distractionsBAD poor displays can lead to mode errorsBAD computers can ___________ (NW 255, DAL 1141: takeoff warning systems failed)
