North Central Indiana's Innovation Landscape / July 2007

I. Home | II. Indiana | III. Region | IV. Innovators' Index | V. University Index | VI. About Patents | VII. Methodology

Note: You can find the most up-to-date version of this study here. This is the archived copy, completed in July 2007.

VII. Methodology

A. Time Periods

1976 is the first year that the USPTO started storing data electronically. No reliable electronic data is available before then. Therefore, 1976 is the starting point of the first time period.

In order to be able to measure how the region is innovating currently compared with in the past, 2 time periods were chosen with 1995 as a cut-off point to mark the beginning of the "modern" era.

For any columns that group patent data by time period (1976-1995 and 1996-2006), the file date of the patent was used to determine which time period the patent belongs in. Most patents take 3 years to go from filing to being issued; because of this variable time period and the fact that the innovation being patented was created close to the file date, it's more accurate to measure the patent by file date.

B. Why Counties?

Many statistical geographic areas exist, including metropolitan and micropolitan statistical areas, cities, and counties. Counties were chosen because more economic, income, education, and poverty statistics are readily available by county.

C. Data Integrity Issues

This report was created with a database of all patents available in electronic form in the state of Indiana. The database was provide by M-CAM, Inc. The County a patent was assigned to was determined by the zip code on the patent, or if no zip code was given, the city the patent was issued in. There were some issues with the data:

Misspellings: Amazingly, a lot of the data in the USPTO database contains misspelled assignee names, city names, etc. The vast majority of these misspellings were filtered and corrected, but a statistically insignificant number may still be present in the data.
Filed but not issued: The data included a small number of patent applications that have been filed but not yet issued. These patents may or may not be issued once the USPTO makes a final determination. However, because the number of patents in this category is so small, the effect is negligible.