The Futility of Bias-Free Learning and Search

  • George D. MontañezEmail author
  • Jonathan Hayase
  • Julius Lauw
  • Dominique Macias
  • Akshay Trikha
  • Julia Vendemiatti
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11919)


Building on the view of machine learning as search, we demonstrate the necessity of bias in learning, quantifying the role of bias (measured relative to a collection of possible datasets, or more generally, information resources) in increasing the probability of success. For a given degree of bias towards a fixed target, we show that the proportion of favorable information resources is strictly bounded from above. Furthermore, we demonstrate that bias is a conserved quantity, such that no algorithm can be favorably biased towards many distinct targets simultaneously. Thus bias encodes trade-offs. The probability of success for a task can also be measured geometrically, as the angle of agreement between what holds for the actual task and what is assumed by the algorithm, represented in its bias. Lastly, finding a favorably biasing distribution over a fixed set of information resources is provably difficult, unless the set of resources itself is already favorable with respect to the given task and algorithm.


Machine learning Inductive bias Algorithmic search 


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.AMISTAD LabHarvey Mudd CollegeClaremontUSA

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