We present a probabilistic extension to active path analyses of token causation (Halpern & Pearl 2001, forthcoming; Hitchcock 2001). The extension uses the generalized notion of intervention presented in (Korb et al. 2004): we allow an intervention to set any probability distribution over the intervention variables, not just a single value. The resulting account can handle a wide range of examples. We do not claim the account is complete --- only that it fills an obvious gap in previous active-path approaches. (...) It still succumbs to recent counterexamples by Hiddleston (2005), because it does not explicitly consider causal processes. We claim three benefits: a detailed comparison of three active-path approaches, a probabilistic extension for each, and an algorithmic formulation. (shrink)

I discuss candidates for definitions of determinism in the context of general relativistic spacetimes, and argue that a definition which does not make recourse to any particular region of spacetime should be preferred over alternatives; one such notion is discussed in detail in the light of various physical examples. The emerging picture of determinism is a pluralist one: sometimes there is no unique way of making our intuitive concept of determinism precise. Instead, what is crucial for assessment of determinism of (...) the theory are auxiliary conditions under which it counts as deterministic or indeterministic, and justification for using them in a given situation. (shrink)

We present a minimum message length (MML) framework for trajectory partitioning by point selection, and use it to automatically select the tolerance parameter ε for Douglas-Peucker partitioning, adapting to local trajectory complexity. By examining a range of ε for synthetic and real trajectories, it is easy to see that the best ε does vary by trajectory, and that the MML encoding makes sensible choices and is robust against Gaussian noise. We use it to explore the identification of micro-activities within a (...) longer trajectory. This MML metric is comparable to the TRACLUS metric – and shares the constraint of abstracting only by omission of points – but is a true lossless encoding. Such encoding has several theoretical advantages – particularly with very small segments (high frame rates) – but actual performance interacts strongly with the search algorithm. Both differ from unconstrained piecewise linear approximations, including other MML formulations. (shrink)

Computer-based argument mapping greatly enhances student critical thinking, more than tripling absolute gains made by other methods. I describe the method and my experience as an outsider. Argument mapping often showed precisely how students were erring (for example: confusing helping premises for separate reasons), making it much easier for them to fix their errors.

The investigation of probabilistic causality has been plagued by a variety of misconceptions and misunderstandings. One has been the thought that the aim of the probabilistic account of causality is the reduction of causal claims to probabilistic claims. Nancy Cartwright (1979) has clearly rebutted that idea. Another ill-conceived idea continues to haunt the debate, namely the idea that contextual unanimity can do the work of objective homogeneity. It cannot. We argue that only objective homogeneity in combination with a causal interpretation (...) of Bayesian networks can provide the desired criterion of probabilistic causality. (shrink)

Two interesting “no hole” spacetime properties, not being future nakedly singular) are unstable in the fine topology.

Using Bayesian network causal models, we provide a simple general account of probabilistic causal interaction. We also detail problems in the leading accounts by Ellery Eells, and any others which require valence reversals, contextual unanimity, or average effects.

Determinism fails easily if spacetimes with points removed from the spacetime manifold are taken to be physically reasonable representations of a way the world could be according to classical general relativity. I discuss a recently proposed condition for determining which spacetimes have holes—epistemic hole freeness—and show that epistemic hole freeness gives the correct verdict in some non-globally hyperbolic spacetimes with a closed subset removed, certain spacetimes with genuinely indeterministic features count as having an epistemic hole, which implies that the requirement (...) of epistemic hole freeness enforces a form of determinism, and there is a large class of spacetimes that intuitively are radically indeterministic and unphysical due to containing a hole, but are free from epistemic holes. I show that a few natural ways of remedying are not satisfactory. (shrink)

ABSTRACT Capital regulations stemming from the Basel accords created incentives for banks to securitize mortgages, even risky ones; hold them at a correspondingly low Basel risk weight; or shift them off of banks' balance sheets to obtain even greater leverage. Securitization was praised by economists and regulators for dispersing risks to investors across the world, providing greater resilience to the financial system. However, since in reality banks tended to hold onto securitized assets—either on their balance sheets or off of them, (...) in off‐balance‐sheet entities—the accumulated credit risk remained with the banks, especially in the “shadow banking sector.” This explains the heightened vulnerability of the financial system to a sudden collapse. (shrink)

The inherent complexity of modern financial systems, and their basis in human behavior, make it hard to establish unequivocally the “who, what, where, when, and why” of the global financial crisis. However, after almost a decade, we know enough to discard much of what has, in the meantime, become folk wisdom about the causes of the debacle, including Wall Street bonus culture, bankers’ greed, the moral hazard of “too big to fail,” government intervention (“too much government”) and deregulation (“not enough (...) government”). While each of these factors may have played some role, the crisis can be much more accurately described as one of ignorance than malevolence. The common thread tying the emergence of the bubble to the disastrous consequences of its bursting is the misunderstanding of correlation and causation links in three key domains: economic policy, financial modeling, and the regulatory framework. These misunderstandings helped fuel the housing bubble and introduced fragility into the system, making it vulnerable to the bubble’s subsequent, unavoidable burst. (shrink)

Part of our fascination with the Maya can be attributed to the fact that they were literate . . . that is, the Classic Maya possessed a visible language that consisted of letters and a grammar, and one of the products of their literacy was the book. (Aveni 1992b, p.3).

We discuss three philosophically interesting epistemic peculiarities of black hole astrophysics: (1) issues concerning whether and in what sense black holes do exist; (2) how to best approach multiplicity of available definitions of black holes; (3) short (i.e., accessible within an individual human lifespan) dynamical timescales present in many of the recent, as well as prospective, observations involving black holes. In each case we argue that the prospects for our epistemic situation are optimistic.

This is an English translation of Juliusz Domański’s “Fausta Socyna Explicatio primae partis primi capitis Euangelii Ioannis i egzegeza erazmiańska,” in his "Erasmiana minora. Studia i szkice o pisarstwie filozoficznym i religijnym Erazma z Rotterdamu" (Warsaw: Instytut Tomistyczny, Instytut Filologii Klasycznej UW, 2017), 337–63. Translated with the Author’s permission. The paper compares the method of Biblical interpretation used by Erasmus of Rotterdam with the method of Socinus, raising the question of the extent to which the method outlined by Socinus (...) in his Explicatio primae partis primi capitis Euangelii Joannis can be seen as continuous and and consonant with the method of Erasmus, and to what extent it should be seen as its rejection or modification. In addition, the essay outlines similarities and differences, with respect to both method and content, between Erasmus' Adnotationes and Socinus’ Explicatio. (shrink)

James McAllister’s 2003 article, “Algorithmic randomness in empirical data” claims that empirical data sets are algorithmically random, and hence incompressible. We show that this claim is mistaken. We present theoretical arguments and empirical evidence for compressibility, and discuss the matter in the framework of Minimum Message Length (MML) inference, which shows that the theory which best compresses the data is the one with highest posterior probability, and the best explanation of the data.