Weissman score
The Weissman score is a performance metric for lossless compression applications. It was developed by Tsachy Weissman, a professor at Stanford University, and Vinith Misra, a graduate student, at the request of producers for HBO's television series Silicon Valley, a television show about a fictional tech start-up working on a data compression algorithm. It compares both required time and compression ratio of measured applications, with those of a de facto standard according to the data type.
The formula is the following; where r is the compression ratio, T is the time required to compress, the overlined ones are the same metrics for a standard compressor, and alpha is a scaling constant.
The Weissman score has been used by Daniel Reiter Horn and Mehant Baid of Dropbox to explain real-world work on lossless compression. According to the authors it "favors compression speed over ratio in most cases."
Example
This example shows the score for the data of the Hutter Prize, using the paq8f as a standard and 1 as the scaling constant.| Application | Compression ratio | Compression time | Weissman score |
| paq8f | 5.467600 | 300 | 1.000000 |
| raq8g | 5.514990 | 420 | 0.720477 |
| paq8hkcc | 5.682593 | 300 | 1.039321 |
| paq8hp1 | 5.692566 | 300 | 1.041145 |
| paq8hp2 | 5.750279 | 300 | 1.051701 |
| paq8hp3 | 5.800033 | 300 | 1.060801 |
| paq8hp4 | 5.868829 | 300 | 1.073826 |
| paq8hp5 | 5.917719 | 300 | 1.082325 |
| paq8hp6 | 5.976643 | 300 | 1.093102 |
| paq8hp12 | 6.104276 | 540 | 0.620247 |
| decomp8 | 6.261574 | 540 | 0.63623 |
| decomp8 | 6.276295 | 540 | 0.637726 |