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Aging and Creative Productivity


 Is There an Age Decrement or Not?
Brief history: Antiquity of topic

 Quételet (1835)
 Beard (1874)
 Lehman (1953)
 Dennis (1966)
 Simonton (1975, 1988, 1997, 2000,
 2004)
Central findings:
The typical age curve


Described by fitting an equation derived
  from a combinatorial model of the
           creative process
Henri Poincaré (1921):
Ideas rose in crowds; I felt them collide
until pairs interlocked, so to speak,
making a stable combination.
[These ideas are like] the hooked atoms
of Epicurus [that collide] like the
molecules of gas in the kinematic theory
of gases [so that] their mutual impacts
may produce new combinations.
p (t) = c (e – at – e – bt)
    where p (t) is productivity at career age t (in years),
    e is the exponential constant (~ 2.718),
    a the typical ideation rate for the domain (0 < a < 1),
    b the typical elaboration rate for the domain (0 < b < 1),
    c = abm/(b – a), where m is the individual’s creative
    potential (i.e. maximum number of publications in indefinite
    lifetime).
[N.B.: If a = b, then p (t) = a2mte – at]
2.0

               1.5
Productivity


               1.0

               0.5

               0.0
                  0    20    40    60
                      Career Age
Central findings:
The typical age curve
 Rapid ascent (decelerating)
Central findings:
The typical age curve
 Rapid ascent (decelerating)
 Single peak
2.0

               1.5
Productivity


               1.0

               0.5

               0.0
                  0    20    40    60
                      Career Age
Central findings:
The typical age curve
 Rapid ascent (decelerating)
 Single peak
 Gradual decline (asymptotic)
2.0

               1.5
Productivity


               1.0

               0.5

               0.0
                  0    20    40    60
                      Career Age
With correlations with published
   data between .95 and .99.
Criticisms of findings:
Is the age decrement real?
Criticisms of findings:
Is the age decrement real?
 Quality but not quantity?
Criticisms of findings:
Is the age decrement real?
 Quality but not quantity?
  – But high correlation between two
Criticisms of findings:
Is the age decrement real?
 Quality but not quantity?
 Differential competition?
Criticisms of findings:
Is the age decrement real?
 Quality but not quantity?
 Differential competition?
  – But survives statistical controls
Criticisms of findings:
Is the age decrement real?
 Quality but not quantity?
 Differential competition?
 Aggregation error?
Criticisms of findings:
Is the age decrement real?
 Quality but not quantity?
 Differential competition?
 Aggregation error?
  – But persists at individual level
e.g., the career of Thomas Edison

 CEdison (t) = 2595(e   - .044t
                                  -e         )
                                       - .058t



             r = .74
500


          400
                          Observed Count
                          Predicted Count
          300
Patents




          200


          100


           0
            0   10 20 30 40 50 60 70 80
                      Career Age
However ...
Complicating considerations
Complicating considerations

 Individual differences
Complicating considerations

 Individual differences
 – Creative potential (m in model)
0.5

             0.4          Gerontology/Geriatrics
                          Geology
                          Infantile Paralysis
Proportion


             0.3          Chemistry
                          Psychology
             0.2

             0.1

             0.0
                   1 2 3 4 5 6 7 8 9 10 11 12
                            Decile
In fact,
1) cross-sectional variation always
appreciably greater than longitudinal
variation
2) the lower an individual’s
productivity the more random the
longitudinal distribution becomes
Complicating considerations

 Individual differences
 – Creative potential
 – Age at career onset (i.e., chronological age
   at t = 0 in model)
Hence, arises a two-dimensional
 typology of career trajectories
High Creative Early Bloomers                               Low Creative Early Bloomers
                        5                                                          5


Creative Productivity




                                                           Creative Productivity
                        4                                                          4
                        3      f    b       l                                      3
                        2                                                          2
                                                                                            f b    l
                        1                                                          1
                        0                                                          0
                        20 30 40 50 60 70 80 90                                    20 30 40 50 60 70 80 90
                          Chronological Age                                          Chronological Age
                            High Creative Late Bloomers                                Low Creative Late Bloomers
                        5                                                          5
Creative Productivity




                                                           Creative Productivity
                        4                                                          4
                        3          f    b       l                                  3
                        2                                                          2
                                                                                                f b l
                        1                                                          1
                        0                                                          0
                        20 30 40 50 60 70 80 90                                    20 30 40 50 60 70 80 90
                          Chronological Age                                          Chronological Age
Complicating considerations

Individual differences
Quantity-quality relation
Complicating considerations

Individual differences
Quantity-quality relation
 – The equal-odds rule
Complicating considerations

Individual differences
Quantity-quality relation
 – The equal-odds rule
 – Career landmarks
Complicating considerations

Individual differences
Quantity-quality relation
 – The equal-odds rule
 – Career landmarks:
   • First major contribution (f)
High Creative Early Bloomers                               Low Creative Early Bloomers
                        5                                                          5


Creative Productivity




                                                           Creative Productivity
                        4                                                          4
                        3      f    b       l                                      3
                        2                                                          2
                                                                                            f b    l
                        1                                                          1
                        0                                                          0
                        20 30 40 50 60 70 80 90                                    20 30 40 50 60 70 80 90
                          Chronological Age                                          Chronological Age
                            High Creative Late Bloomers                                Low Creative Late Bloomers
                        5                                                          5
Creative Productivity




                                                           Creative Productivity
                        4                                                          4
                        3          f    b       l                                  3
                        2                                                          2
                                                                                                f b l
                        1                                                          1
                        0                                                          0
                        20 30 40 50 60 70 80 90                                    20 30 40 50 60 70 80 90
                          Chronological Age                                          Chronological Age
Complicating considerations

Individual differences
Quantity-quality relation
 – The equal-odds rule
 – Career landmarks:
   • First major contribution (f)
   • Single best contribution (b)
High Creative Early Bloomers                               Low Creative Early Bloomers
                        5                                                          5


Creative Productivity




                                                           Creative Productivity
                        4                                                          4
                        3      f    b       l                                      3
                        2                                                          2
                                                                                            f b    l
                        1                                                          1
                        0                                                          0
                        20 30 40 50 60 70 80 90                                    20 30 40 50 60 70 80 90
                          Chronological Age                                          Chronological Age
                            High Creative Late Bloomers                                Low Creative Late Bloomers
                        5                                                          5
Creative Productivity




                                                           Creative Productivity
                        4                                                          4
                        3          f    b       l                                  3
                        2                                                          2
                                                                                                f b l
                        1                                                          1
                        0                                                          0
                        20 30 40 50 60 70 80 90                                    20 30 40 50 60 70 80 90
                          Chronological Age                                          Chronological Age
Complicating considerations

Individual differences
Quantity-quality relation
 – The equal-odds rule
 – Career landmarks:
   • First major contribution (f)
   • Single best contribution (b)
   • Last major contribution(l)
High Creative Early Bloomers                               Low Creative Early Bloomers
                        5                                                          5


Creative Productivity




                                                           Creative Productivity
                        4                                                          4
                        3      f    b       l                                      3
                        2                                                          2
                                                                                            f b    l
                        1                                                          1
                        0                                                          0
                        20 30 40 50 60 70 80 90                                    20 30 40 50 60 70 80 90
                          Chronological Age                                          Chronological Age
                            High Creative Late Bloomers                                Low Creative Late Bloomers
                        5                                                          5
Creative Productivity




                                                           Creative Productivity
                        4                                                          4
                        3          f    b       l                                  3
                        2                                                          2
                                                                                                f b l
                        1                                                          1
                        0                                                          0
                        20 30 40 50 60 70 80 90                                    20 30 40 50 60 70 80 90
                          Chronological Age                                          Chronological Age
Journalist Alexander Woolcott
     reporting on G. B. Shaw:
“At 83 Shaw’s mind was perhaps
not quite as good as it used to be.
  It was still better than anyone
               else’s.”
Complicating considerations

 Individual differences
 Quantity-quality relation
 Inter-domain contrasts (a and b in
 model)
Complicating considerations

 Individual differences
 Quantity-quality relation
 Inter-domain contrasts
 – Differential decrements (0-100%)
30
Percent of Total Lifetime Output




                                   20




                                   10
                                                   SCHOLARS
                                                   SCIENTISTS
                                                   ARTISTS

                                    0
                                    10   20   30     40 50 60   70   80
                                                   Age Decade
Complicating considerations

 Individual differences
 Quantity-quality relation
 Inter-domain contrasts
 – Differential peaks and decrements
 – Differential landmark placements
First Major Contribution
                                 Best Contribution
                                 Last Major Contribution
                    60



Chronological Age   50



                    40



                    30



                    20
                            y    gy   ry ce    s     e    cs gy
                          om iolo mist ien atic dicin hysi olo
                        on B he osc em e             P chn
                     str        C Ge     ath  M
                    A
                                        M              Te
                                     DISCIPLINE
Complicating considerations

 Individual differences
 Quantity-quality relation
 Inter-domain contrasts
 Impact of extraneous factors
Complicating considerations

 Individual differences
 Quantity-quality relation
 Inter-domain contrasts
 Impact of extraneous factors
 – Negative influences
Complicating considerations

 Individual differences
 Quantity-quality relation
 Inter-domain contrasts
 Impact of extraneous factors
 – Negative influences: e.g., war
Complicating considerations

 Individual differences
 Quantity-quality relation
 Inter-domain contrasts
 Impact of extraneous factors
 – Negative influences
 – Positive influences
Complicating considerations

 Individual differences
 Quantity-quality relation
 Inter-domain contrasts
 Impact of extraneous factors
 – Negative influences
 – Positive influences: e.g.,
    • disciplinary networks
Complicating considerations

 Individual differences
 Quantity-quality relation
 Inter-domain contrasts
 Impact of extraneous factors
 – Negative influences
 – Positive influences: e.g.,
    • disciplinary networks
    • cross-fertilization
Hence, the creative productivity
within any given career will show
major departures from expectation,
 some positive and some negative
Three Main Conclusions

 Age decrement a highly predictable
 phenomenon at the aggregate level
 Age decrement far more unpredictable
 at the individual level
 Age decrement probably less due to
 aging per se than to other factors both
 intrinsic and extrinsic to the creative
 process
Hence, the possibility of late-life
creative productivity increments;
              e.g.,
    Michel-Eugène Chevreul
           (1786-1889)
References

 Simonton, D. K. (1984). Creative productivity
 and age: A mathematical model based on a
 two-step cognitive process. Developmental
 Review, 4, 77-111.
 Simonton, D. K. (1989). Age and creative
 productivity: Nonlinear estimation of an
 information-processing model. International
 Journal of Aging and Human Development,
 29, 23-37.
References
 Simonton, D. K. (1991). Career landmarks in science:
 Individual differences and interdisciplinary contrasts.
 Developmental Psychology, 27, 119-130.
 Simonton, D. K. (1997). Creative productivity: A
 predictive and explanatory model of career
 trajectories and landmarks. Psychological Review,
 104, 66-89.
 Simonton, D. K. (2004). Creativity in science:
 Chance, logic, genius, and zeitgeist. Cambridge,
 England: Cambridge University Press.
test+ppt+2

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test+ppt+2

  • 1. Aging and Creative Productivity Is There an Age Decrement or Not?
  • 2. Brief history: Antiquity of topic Quételet (1835) Beard (1874) Lehman (1953) Dennis (1966) Simonton (1975, 1988, 1997, 2000, 2004)
  • 3. Central findings: The typical age curve Described by fitting an equation derived from a combinatorial model of the creative process
  • 4. Henri Poincaré (1921): Ideas rose in crowds; I felt them collide until pairs interlocked, so to speak, making a stable combination. [These ideas are like] the hooked atoms of Epicurus [that collide] like the molecules of gas in the kinematic theory of gases [so that] their mutual impacts may produce new combinations.
  • 5. p (t) = c (e – at – e – bt) where p (t) is productivity at career age t (in years), e is the exponential constant (~ 2.718), a the typical ideation rate for the domain (0 < a < 1), b the typical elaboration rate for the domain (0 < b < 1), c = abm/(b – a), where m is the individual’s creative potential (i.e. maximum number of publications in indefinite lifetime). [N.B.: If a = b, then p (t) = a2mte – at]
  • 6. 2.0 1.5 Productivity 1.0 0.5 0.0 0 20 40 60 Career Age
  • 7. Central findings: The typical age curve Rapid ascent (decelerating)
  • 8.
  • 9. Central findings: The typical age curve Rapid ascent (decelerating) Single peak
  • 10. 2.0 1.5 Productivity 1.0 0.5 0.0 0 20 40 60 Career Age
  • 11. Central findings: The typical age curve Rapid ascent (decelerating) Single peak Gradual decline (asymptotic)
  • 12. 2.0 1.5 Productivity 1.0 0.5 0.0 0 20 40 60 Career Age
  • 13. With correlations with published data between .95 and .99.
  • 14. Criticisms of findings: Is the age decrement real?
  • 15. Criticisms of findings: Is the age decrement real? Quality but not quantity?
  • 16. Criticisms of findings: Is the age decrement real? Quality but not quantity? – But high correlation between two
  • 17. Criticisms of findings: Is the age decrement real? Quality but not quantity? Differential competition?
  • 18. Criticisms of findings: Is the age decrement real? Quality but not quantity? Differential competition? – But survives statistical controls
  • 19. Criticisms of findings: Is the age decrement real? Quality but not quantity? Differential competition? Aggregation error?
  • 20. Criticisms of findings: Is the age decrement real? Quality but not quantity? Differential competition? Aggregation error? – But persists at individual level
  • 21. e.g., the career of Thomas Edison CEdison (t) = 2595(e - .044t -e ) - .058t r = .74
  • 22. 500 400 Observed Count Predicted Count 300 Patents 200 100 0 0 10 20 30 40 50 60 70 80 Career Age
  • 26. Complicating considerations Individual differences – Creative potential (m in model)
  • 27. 0.5 0.4 Gerontology/Geriatrics Geology Infantile Paralysis Proportion 0.3 Chemistry Psychology 0.2 0.1 0.0 1 2 3 4 5 6 7 8 9 10 11 12 Decile
  • 28. In fact, 1) cross-sectional variation always appreciably greater than longitudinal variation 2) the lower an individual’s productivity the more random the longitudinal distribution becomes
  • 29. Complicating considerations Individual differences – Creative potential – Age at career onset (i.e., chronological age at t = 0 in model)
  • 30. Hence, arises a two-dimensional typology of career trajectories
  • 31. High Creative Early Bloomers Low Creative Early Bloomers 5 5 Creative Productivity Creative Productivity 4 4 3 f b l 3 2 2 f b l 1 1 0 0 20 30 40 50 60 70 80 90 20 30 40 50 60 70 80 90 Chronological Age Chronological Age High Creative Late Bloomers Low Creative Late Bloomers 5 5 Creative Productivity Creative Productivity 4 4 3 f b l 3 2 2 f b l 1 1 0 0 20 30 40 50 60 70 80 90 20 30 40 50 60 70 80 90 Chronological Age Chronological Age
  • 34. Complicating considerations Individual differences Quantity-quality relation – The equal-odds rule – Career landmarks
  • 35. Complicating considerations Individual differences Quantity-quality relation – The equal-odds rule – Career landmarks: • First major contribution (f)
  • 36. High Creative Early Bloomers Low Creative Early Bloomers 5 5 Creative Productivity Creative Productivity 4 4 3 f b l 3 2 2 f b l 1 1 0 0 20 30 40 50 60 70 80 90 20 30 40 50 60 70 80 90 Chronological Age Chronological Age High Creative Late Bloomers Low Creative Late Bloomers 5 5 Creative Productivity Creative Productivity 4 4 3 f b l 3 2 2 f b l 1 1 0 0 20 30 40 50 60 70 80 90 20 30 40 50 60 70 80 90 Chronological Age Chronological Age
  • 37. Complicating considerations Individual differences Quantity-quality relation – The equal-odds rule – Career landmarks: • First major contribution (f) • Single best contribution (b)
  • 38. High Creative Early Bloomers Low Creative Early Bloomers 5 5 Creative Productivity Creative Productivity 4 4 3 f b l 3 2 2 f b l 1 1 0 0 20 30 40 50 60 70 80 90 20 30 40 50 60 70 80 90 Chronological Age Chronological Age High Creative Late Bloomers Low Creative Late Bloomers 5 5 Creative Productivity Creative Productivity 4 4 3 f b l 3 2 2 f b l 1 1 0 0 20 30 40 50 60 70 80 90 20 30 40 50 60 70 80 90 Chronological Age Chronological Age
  • 39. Complicating considerations Individual differences Quantity-quality relation – The equal-odds rule – Career landmarks: • First major contribution (f) • Single best contribution (b) • Last major contribution(l)
  • 40. High Creative Early Bloomers Low Creative Early Bloomers 5 5 Creative Productivity Creative Productivity 4 4 3 f b l 3 2 2 f b l 1 1 0 0 20 30 40 50 60 70 80 90 20 30 40 50 60 70 80 90 Chronological Age Chronological Age High Creative Late Bloomers Low Creative Late Bloomers 5 5 Creative Productivity Creative Productivity 4 4 3 f b l 3 2 2 f b l 1 1 0 0 20 30 40 50 60 70 80 90 20 30 40 50 60 70 80 90 Chronological Age Chronological Age
  • 41. Journalist Alexander Woolcott reporting on G. B. Shaw: “At 83 Shaw’s mind was perhaps not quite as good as it used to be. It was still better than anyone else’s.”
  • 42. Complicating considerations Individual differences Quantity-quality relation Inter-domain contrasts (a and b in model)
  • 43. Complicating considerations Individual differences Quantity-quality relation Inter-domain contrasts – Differential decrements (0-100%)
  • 44. 30 Percent of Total Lifetime Output 20 10 SCHOLARS SCIENTISTS ARTISTS 0 10 20 30 40 50 60 70 80 Age Decade
  • 45. Complicating considerations Individual differences Quantity-quality relation Inter-domain contrasts – Differential peaks and decrements – Differential landmark placements
  • 46. First Major Contribution Best Contribution Last Major Contribution 60 Chronological Age 50 40 30 20 y gy ry ce s e cs gy om iolo mist ien atic dicin hysi olo on B he osc em e P chn str C Ge ath M A M Te DISCIPLINE
  • 47. Complicating considerations Individual differences Quantity-quality relation Inter-domain contrasts Impact of extraneous factors
  • 48. Complicating considerations Individual differences Quantity-quality relation Inter-domain contrasts Impact of extraneous factors – Negative influences
  • 49. Complicating considerations Individual differences Quantity-quality relation Inter-domain contrasts Impact of extraneous factors – Negative influences: e.g., war
  • 50. Complicating considerations Individual differences Quantity-quality relation Inter-domain contrasts Impact of extraneous factors – Negative influences – Positive influences
  • 51. Complicating considerations Individual differences Quantity-quality relation Inter-domain contrasts Impact of extraneous factors – Negative influences – Positive influences: e.g., • disciplinary networks
  • 52. Complicating considerations Individual differences Quantity-quality relation Inter-domain contrasts Impact of extraneous factors – Negative influences – Positive influences: e.g., • disciplinary networks • cross-fertilization
  • 53. Hence, the creative productivity within any given career will show major departures from expectation, some positive and some negative
  • 54. Three Main Conclusions Age decrement a highly predictable phenomenon at the aggregate level Age decrement far more unpredictable at the individual level Age decrement probably less due to aging per se than to other factors both intrinsic and extrinsic to the creative process
  • 55. Hence, the possibility of late-life creative productivity increments; e.g., Michel-Eugène Chevreul (1786-1889)
  • 56. References Simonton, D. K. (1984). Creative productivity and age: A mathematical model based on a two-step cognitive process. Developmental Review, 4, 77-111. Simonton, D. K. (1989). Age and creative productivity: Nonlinear estimation of an information-processing model. International Journal of Aging and Human Development, 29, 23-37.
  • 57. References Simonton, D. K. (1991). Career landmarks in science: Individual differences and interdisciplinary contrasts. Developmental Psychology, 27, 119-130. Simonton, D. K. (1997). Creative productivity: A predictive and explanatory model of career trajectories and landmarks. Psychological Review, 104, 66-89. Simonton, D. K. (2004). Creativity in science: Chance, logic, genius, and zeitgeist. Cambridge, England: Cambridge University Press.