In the last few years, there has been a growing shift towards the analytics side of basketball. Formerly unknown analytics maestros like Daryl Morey are now becoming more recognized, and their principles are being used to build teams that can contend for championships.
A core tenet of sports analytics is stripping away the bias that is inherently present in humans, allowing for an evaluation of players at face value. Though the sports analytics movement has gained traction in NBA circles, many fans still haven’t embraced it, which precludes them from understanding certain trades and signings made by their favorite teams.
One way to eliminate bias without the benefit of supercomputers and reams of data is through using cryptography to encrypt players’ names. This ensures that players are evaluated only based on their stats.
Cryptographyinvolves coding the plain text to make it secure and decoding the coded text to retrieve the plain text. The coding and decoding processes are accomplished using keys.
There are primarily two types of encryption: Symmetric key and Asymmetric key encryption.
Symmetric key encryptioninvolves the use of the same key for both encryption and decryption. Symmetric key encryption can be broken if others know the key, which makes it vulnerable. One example of Symmetric key encryption is the Advanced Encryption Standard (AES).
Asymmetric key encryptioninvolves the use of two keys, a public key to encrypt the plain text and a private key to decrypt the coded text. Asymmetric key encryption is harder to break than symmetric key encryption, but it also takes more time and computing power, due to the magnitude of the numbers involved. One example of Asymmetric key encryption is the RSA cryptosystem.
The RSA cryptosystemwas invented by Ron Rivest, Adi Shamir, and Leonard Adleman in 1977. The name RSA comes from the first letter of the authors’ last names. The keys to encrypt and decrypt are generated by multiplying two large prime numbers. Though the formulae to generate the public and private keys are common knowledge, the difficulty in deriving the public and private keys lies in the time and computing power required to factorize the product of two large prime numbers.
In the RSA system, every participant uses two keys, public and private, to encrypt and decrypt plain text. As the names suggest, a private key is known only to the person while the public key of a person is known to all participants. The person encrypting the text uses the recipient’s public key to encrypt the plain text. The recipient uses their private key to decrypt the encrypted text. As the recipient’s private key is known only to the recipient, no one other than the recipient can decrypt the message easily.
Using the RSA module in a simple Python program, I generated public and private keys. I then encrypted a plain text, like the name Kawhi Leonard, resulting in the following bytes. The public key used to encrypt the plain text is this:
The plain text, Kawhi Leonard, when encrypted with the public key, looks something like this:
To decrypt the bytes to get the plain text, I use the private key. Of course, I am not publishing the private key here as it is supposed to be private.
In a previous article, I wrote about how the San Antonio Spurs, using a linear regression model, can aim for another NBA championship. The table in this article listed combinations of the Spurs starting five and their predicted win-coefficients. Encrypting the players’ names will give us this table:
For reference, this is the table with the players’ names:
If the encrypted text is too large to fit in a page or sometimes even store efficiently, we can use Base64 encoding to create coded text that is smaller than encrypted text. This is space friendly, but it is easy to reverse, and does not provide much in the way of security.
For example, encoding the text Kawhi Leonard via Base64 results in the encoded text:
Using a Base64 decoder, we can get the plain text from the encoded text.
Thus, using cryptography, we can strip out the bias that is inherent in humans, allowing for a more objective evaluation of players’ talents, and maybe even learn a thing or two about coding, a very interesting subject in its own right!
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