Pictorial and Verbal Representation of Route Information

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Pictorial and Verbal Representation ofRoute
Information

• Paul Lee Barbara Tversky
• Stanford University

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Picture is worth a thousand words.

• Underlying Assumptions
• Depictions (e.g. diagrams, maps) fundamentally
  different than descriptions (e.g. texts,
  directions).
• Depictions better than descriptions
• But
• For certain tasks (e.g. route wayfinding),
  depictions and descriptions convey similar
  information.

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Route Maps Route Directions

• Are the schematizations similar?
• Ask students outside dorm how to get to Taco Bell

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Sketch Map 1
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Sketch Map 2
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Directions 1

• From Roble parking lot
• R onto Santa Theresa
• L onto Lagunita (the first stop sign)
• L onto Mayfield
• R onto Bowdoin
• L onto Stanford Ave
• R onto El Camino
• go down a few miles. Its on the right.

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Direction 2
Go down street toward main campus (where most of
the buildings are as opposed to where the fields
are) make a right on the first real street (not
an entrance to a dorm or anything else). Then
make a left on the 2nd street you come to. There
should be some buildings on your right (Flo Mo)
and a parking lot on your left. the street will
make a sharp right. Stay on it. That puts you
on Mayfield Rd. The first intersection after the
turn will be at Campus Dr. Turn left and stay
until you get to El Camino. Turn right (south)
and Taco Bell is a few miles down on the right.
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Segmentation according to Denis

• Start point you leave the building
• Reorientation you turn left
• Path/progression you follow Main St.
• End point until you get to the restaurant

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Was all necessary information included?

• Maps Yes
• Directions No, incomplete explicitly
• 75 lacked start or end point
• 45 lacked path/progression information
• Missing information recovered by 2 rules
• Continuity
• Forward progression

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Was extra information included?

• Yes, in 90 of maps and directions
• Added information kept traveler on track
• cardinal directions
• arrows
• distances
• extra landmarks

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Path Types Text vs. Depiction
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Goodness Ratings

• 23 Subjects rated the goodness of the maps and
  directions
• 1-7 rating scale 1not usable 7excellent

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Good Map 1 (rating 5.73)
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Good Map 2 (rating 5.50)
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Avg. Map 1 (rating 3.73)
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Avg. Map 2 (rating 3.68)
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Bad Map 1 (rating 2.68)
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Bad Map 2 (rating 2.23)
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Good Direction (5.59)

• From Roble fields head out towards campus
• at Campus drive turn right
• follow Campus around until you hit palm drive
• turn left onto palm drive
• go on palm until you hit el camino
• turn rt. Onto el camino (its one of those things
  where you merge right)
• head south on el camino
• pass several lights (2.3)
• Taco Bell will be on your right, on the corner of
  some street el camino

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Average Direction (3.73)

• Go out St. Theresa
• turn Rt.
• Follow Campus Dr. way around to Galvez
• turn left on Galvez
• turn right on El Camino
• Go till you see Taco Bell on your right

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Bad Direction (2.68)

• Lomita
• Mayfield --gt Row Houses
• Left onto Campus Drive East
• Follow to SERRA
• rt. on SERRA
• rt. onto EL CAMINO - 2 miles down EL CAMINO

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How was information schematized?

• Start/end points landmarks, paths
• Maps icons, rough shapes, street names
• Directions names, descriptions
• Reorientations amount unspecified
• Maps roughly perpendicular lines, arrows
• Directions turn, take a, make a, go
• Path/progression
• Maps straight or curved line
• Directions go or follow

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Depictive Toolkit

• Intersections
• Straight Paths

• Curved Paths
• Landmarks
• Arrows

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Descriptive Toolkit

• Start at A facing B
• Turn R/L, turn R/L on (x)
• Go down (x), go down (x) until, go down (x) for
  (y)
• Follow, follow until (x), follow (x) for (y)
• Continue past
• Z will be on your L/R

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Toolkit Map 1
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Toolkit Map 2
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Toolkit Map 3
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Toolkit Map 4
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Toolkit Map 5
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Toolkit Direction 1

• Start at Cowell, facing Campus Loop.
• Turn right on Campus loop and follow until Serra
  St.
• Turn right on Serra St.
• Turn left on El Camino Real.
• Go down El Camino Real and Town Country will be
  on your right.

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Toolkit Direction 2

• Start at Cowell Health Center, facing Campus
  drive loop.
• Turn right at Campus Drive.
• Follow Campus Drive until the first stop sign.
• Turn right on Bowdoin.
• Follow Bowdoin until the second stop sign.
• Turn left on Stanford Avenue.
• Go down Stanford Avenue, past 2 lights and a stop
  sign, until you reach the third light (El Camino
  real)
• Turn left on El Camino.
• Follow El Camino (northwest) past 2 stop lights
  for about one mile until you reach Embarcadero.
  (there is a light there)
• Turn right immediately after the light at
  Embarcadero into the T C Plaza.

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Results Depictive Toolkit

• Intersections
• Use of wrong X, L, T intersection - 93 of
  participants
• Most cases X -gt T and T -gt L
• Non-prototypical intersection - 43
• Exit ramps - 57
• Paths
• Used only straight paths (i.e. no curved paths) -
  14
• Non-prototypical paths - 29

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Results Depictive Toolkit

• Landmarks
• Added by participants
• Stop signs/lights - 43
• Overpass - 43
• Iconic landmarks - 21
• Arrows - 86
• Additional Information
• Cardinal direction - 14
• Distance information - 7
• Commentary - 50

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Results Descriptive Toolkit

• Turns
• Alternative wording (e.g. make/take a) - 21of
  participants
• exit at ___ - 43
• Specified turn angles - 50
• Progressions
• Alternative wording (e.g. take, head down, stay
  on, pass, proceed, get on) - 14
• Path description - 57

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Results Descriptive Toolkit

• Landmarks
• Stop signs/lights - 86 of participants
• Overpass - 7
• Dead end - 21
• Parking lot - 14
• Additional Information
• Time/distance information - 71
• Commentary - 29

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Mega-descriptions/depictions

• Denis ideal skeletal descriptions derived from
  mega-descriptions
• Experiment Task
• Subjects receive mega-descriptions or
  mega-depictions of the route
• 12 cross streets and 44 landmarks included
• Subjects are asked to cross out phrases or
  landmarks to create an ideal description or
  depiction
• Skeletal description/depiction created from
  retention of phrases and landmarks by 70 of
  subjects

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Skeletal Depiction
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Skeletal Description

• Directions
• You are standing on Santa Teresa St.
• Take Santa Teresa down.
• Turn right on Lomita.
• Turn left on Mayfield.
• Take Mayfield until the road stops at a stop sign
  and veer right, in front of Xanadu.
• Follow the road to the right.
• At a 4-way stop junction, turn left on Campus Dr.
  East.
• You will come across a 4-way stop junction in
  front of a gas station.
• Turn right on Serra.
• Turn left on El Camino Real and continue for
  about 2-3 miles.
• Once you pass Curtner St, start looking for Taco
  Bell on the right.

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Retained Landmark Types
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Summary

• Similar schematizations for route maps and route
  directions
• Can determine goodness of maps and directions
• Majority of route information can be expressed
  with a small finite set of depictions and
  descriptions