Using Computer Vision to Measure Design Similarity: An Application to Design Rights

This repository contains the data and code pack for the paper "Using Computer Vision to Measure Design Similarity: An Application to Design Rights" submitted to Research Policy.

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📁 Folder Contents

🧮 CODES

1. SSIM.py: Python code to measure the structural similarity index (SSIM), based on Wang et al., 2004.
2. Code.do: Stata code to replicate the transformation from design pairs to design space similarity density (DSSD).

🖼️ IMAGE DATA

• Preprocessed/: A sample of cleaned images of design rights included in USPC Subclass D14-1380AC (Mobile Phones).

📊 STRUCTURED DATA

1. DesignMetaInfo.dta: Design-level application data with USPC class and subclass.
2. DesignPairs*.dta: Design pair similarity chunks (partitioned from 1 to 35) based on SSIM (see DesignPairs/).
3. NearestNeighbor.dta: Design-level average nearest neighbor measures (1-nn, 3-nn, 5-nn).
4. DSSD.dta: Subclass-level data on Design Space Similarity Density.
5. SubclassOutcomeControls.dta: Subclass-level litigation outcomes and control variables.

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📘 Data Dictionary

A. Design Rights Meta Information — DesignMetaInfo.dta

Source: patentsview.org
Note: design2 = design1 by default; the fields aid in merging to similarity data.

Variable	Description
uspc_class	Primary classification under USPC (broad category)
uspc_subclass	Secondary classification under USPC (specific category)
design1	Unique ID for focal design
design2	Unique ID for compared design
date2	Application date of design right

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B. Design Pair Similarity Data (chunked into 35 partitions) — DesignPair*.dta

Source: patentsview.org, SSIM.py

Variable	Description
design1	Focal design ID
design2	Compared design ID
ssim	SSIM-based visual similarity score

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C. Nearest Neighbor — NearestNeighbor.dta

Source: patentsview.org, DesignPair*.dta

Variable	Description
design	Focal design ID
nn_1	SSIM with closest neighbor
nn_3	Average SSIM with top 3 neighbors
nn_5	Average SSIM with top 5 neighbors

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D. DSSD — DSSD.dta

Source: patentsview.org, NearestNeighbor.dta

Variable	Description
uspc_class	Primary USPC classification
uspc_subclass	Secondary USPC classification
year	Calendar year
dssd_5	Avg. SSIM for 5-NN
dssd_3	Avg. SSIM for 3-NN
dssd_1	SSIM for 1-NN

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E. Subclass Litigation Outcome and Control — SubclassOutcomeControls.dta

Variable	Description
uspc_class	Primary USPC classification
uspc_subclass	Secondary USPC classification
year	litigation or application year
subclass_litigation_count	Total designs litigated per subclass-year
subclass_no_unq_designs	Unique design rights per subclass-year
subclass_ave_firm_no_unq_des	Avg. designs per firm in subclass-year
subclass_var_firm_no_unq_des	Variance in firm design filings
subclass_no_unq_atty	Unique attorneys in subclass-year
subclass	Unique subclass identifier