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Urban Start-up Agglomeration and Venture Capital Investment (view source)
Revision as of 11:54, 17 November 2020
, 11:54, 17 November 2020→Heuristic Layer
One complaint made about the heuristic results is that it is near the middle (i.e., it's 48.7717%, which happens to be near 50%). Although the nature of any HCA on geographic coords implies that the result is unlikely to the close to the bounds (0 or 100%) and more likely to be near the middle (50%), it could be in an entirely different place. '''This result (i.e., the heuristic layer at 48.7717%) characterizes the agglomeration of venture-backed startup firms'''. You'd get a very different number if you studied gas stations, supermarkets, airports, or banana plantations!
====Comparing the Hauristic and R2 Layers====
{{Colored box|title=The Case for the Heuristic Method|content=The heuristic method (i.e., using the inflection in the plot from the population of city-year-layers) finds pretty much the same layer as the R2 method with almost no work, and it can be used in a within-city analysis without having to hold hull count constant.}}
numstartups | 15 38.74743 83.6814 3797 6 1317 7 83
----------------------------------------------------------------------------------------------
Analyzing layers:
Method Avg. Layer Index Std. Dev Layer Index
Max R2 0.392473192 0.2380288695
Heuristic 0.43423652 0.0495630531
The Max R2 and Heuristic layers are identical in 12.6% of cases! Some of these cases are found in city-years with a large number of layers, for instance, there are 90 city-years that have more than 20 startups and identical heuristic and max r2 layers. The table below shows city-years with more than 50 startups and identical heuristic and max R2 layers:
{| class="wikitable"
|- style="font-weight:bold;"
! place
! statecode
! year
! numstartups
! chosenhulllayer
! heurflhlayer
|-
| San Francisco
| CA
| 2,009
| 503
| 175
| 175
|-
| Los Angeles
| CA
| 2,012
| 213
| 93
| 93
|-
| Redwood City
| CA
| 2,012
| 151
| 49
| 49
|-
| Redwood City
| CA
| 2,013
| 151
| 49
| 49
|-
| Seattle
| WA
| 2,000
| 113
| 48
| 48
|-
| Houston
| TX
| 2,007
| 92
| 40
| 40
|-
| Waltham
| MA
| 2,012
| 73
| 24
| 24
|-
| Pittsburgh
| PA
| 2,008
| 70
| 25
| 25
|-
| Bellevue
| WA
| 2,001
| 64
| 25
| 25
|-
| Bellevue
| WA
| 2,003
| 61
| 23
| 23
|-
| Pleasanton
| CA
| 2,004
| 54
| 20
| 20
|-
| Menlo Park
| CA
| 2,004
| 52
| 22
| 22
|-
| Durham
| NC
| 2,009
| 50
| 22
| 22
|}
===Another list of items===
