Results 21  30
of
177
Causality and Price Discovery: An Application of Directed Acyclic Graphs
, 2002
"... Directed Acyclic Graphs (DAG's) and Error Correction Models (ECM's) are employed to analyze questions of price discovery between spatially separated commodity markets and the transportation market linking them together. Results from our analysis suggest these markets are highly interconnected but it ..."
Abstract

Cited by 8 (3 self)
 Add to MetaCart
Directed Acyclic Graphs (DAG's) and Error Correction Models (ECM's) are employed to analyze questions of price discovery between spatially separated commodity markets and the transportation market linking them together. Results from our analysis suggest these markets are highly interconnected but it is the inland commodity market that is strongly influenced by both the transportation and commodity export markets. However, the commodity markets affect the volatility of the transportation market over longer horizons. Our results suggest that transportation rates are critical in the price discovery process lending support for the recent development of exchange traded barge rate futures contracts.
Evolutionary Theory and the Reality of Macro Probabilities
"... Evolutionary theory is awash with probabilities. For example, natural selection is said to occur when there is variation in fitness, and fitness is standardly decomposed into two components, viability and fertility, each of which is understood probabilistically. With respect to viability, a fertiliz ..."
Abstract

Cited by 8 (2 self)
 Add to MetaCart
Evolutionary theory is awash with probabilities. For example, natural selection is said to occur when there is variation in fitness, and fitness is standardly decomposed into two components, viability and fertility, each of which is understood probabilistically. With respect to viability, a fertilized egg is said to have a certain chance of surviving to reproductive age; with respect to fertility, an adult is said to have an expected number of offspring. There is more to evolutionary theory than the theory of natural selection, and here too one finds probabilistic concepts aplenty. When there is no selection, the theory of neutral evolution says that a gene’s chance of eventually reaching fixation is 1/(2N), where N is the number of organisms in the generation of the diploid population to which the gene belongs. The evolutionary consequences of mutation are likewise conceptualized in terms of the probability per unit time a gene has of changing from one state to another. The examples just mentioned are all “forwarddirected” probabilities; they describe the probability of later events, conditional on earlier events. However, evolutionary theory also uses “backwards probabilities ” that describe the probability of a cause conditional on its effects; for example, coalescence theory allows one to calculate the expected number of generations in the past that the genes in the present generation find their most recent common
On causally asymmetric versions of Occam’s Razor and their relation to thermodynamics
, 2007
"... and their relation to thermodynamics ..."
Local primitive causality and the common cause principle in quantum field theory, Found
 Phys
, 2002
"... If {A(V)} is a net of local von Neumann algebras satisfying standard axioms of algebraic relativistic quantum field theory and V 1 and V 2 are spacelike separated spacetime regions, then the system (A(V 1), A(V 2), f) is said to satisfy the Weak Reichenbach’s Common Cause Principle iff for every pai ..."
Abstract

Cited by 7 (5 self)
 Add to MetaCart
If {A(V)} is a net of local von Neumann algebras satisfying standard axioms of algebraic relativistic quantum field theory and V 1 and V 2 are spacelike separated spacetime regions, then the system (A(V 1), A(V 2), f) is said to satisfy the Weak Reichenbach’s Common Cause Principle iff for every pair of projections A ¥ A(V 1), B ¥ A(V 2) correlated in the normal state f there exists a projection C belonging to a von Neumann algebra associated with a spacetime region V contained in the union of the backward light cones of V 1 and V 2 and disjoint from both V 1 and V 2, a projection having the properties of a Reichenbachian common cause of the correlation between A and B. It is shown that if the net has the local primitive causality property then every local system (A(V 1), A(V 2), f) with a locally normal and locally faithful state f and suitable bounded V 1 and V 2 satisfies the
Backward steps in rigid body simulation
 ACM TRANS. GRAPH
, 2008
"... Physically based simulation of rigid body dynamics is commonly done by timestepping systems forward in time. In this paper, we propose methods to allow timestepping rigid body systems backward in time. Unfortunately, reversetime integration of rigid bodies involving frictional contact is mathemat ..."
Abstract

Cited by 7 (0 self)
 Add to MetaCart
Physically based simulation of rigid body dynamics is commonly done by timestepping systems forward in time. In this paper, we propose methods to allow timestepping rigid body systems backward in time. Unfortunately, reversetime integration of rigid bodies involving frictional contact is mathematically illposed, and can lack unique solutions. We instead propose timereversed rigid body integrators that can sample possible solutions when unique ones do not exist. We also discuss challenges related to dissipationrelated energy gain, sensitivity to initial conditions, stacking, constraints and articulation, rolling, sliding, skidding, bouncing, high angular velocities, rapid velocity growth from microcollisions, and other problems encountered when going against the usual flow of time.
Nocommoncause EPRlike funny business in branching spacetimes
 PHILOSOPHICAL STUDIES
, 2003
"... There is "no EPRlike funny business" if (contrary to apparent fact) our world is as indeterministic as you wish, but is free from the EPRlike quantummechanical phenomena such as is sometimes described in terms of superluminal causation or correlation between distant events. The theory of bran ..."
Abstract

Cited by 7 (4 self)
 Add to MetaCart
There is "no EPRlike funny business" if (contrary to apparent fact) our world is as indeterministic as you wish, but is free from the EPRlike quantummechanical phenomena such as is sometimes described in terms of superluminal causation or correlation between distant events. The theory of branching spacetimes can be used to sharpen the theoretical dichotomy between "EPRlike funny business" and "no EPRlike funny business." Belnap 2002 offered
Time series estimation of the effects of natural experiments
 Journal of Econometrics
, 2006
"... Abstract This paper investigates methods for estimating the effects of natural experiments, especially those created by an intervention or structural change occurring at a specific point in time, such as a government policy intervention, a merger, or the formation or disintegration of a cartel. We d ..."
Abstract

Cited by 7 (6 self)
 Add to MetaCart
Abstract This paper investigates methods for estimating the effects of natural experiments, especially those created by an intervention or structural change occurring at a specific point in time, such as a government policy intervention, a merger, or the formation or disintegration of a cartel. We draw on the extensive literature of
The role of causal models in analogical inference
 Journal of Experimental Psychology: Learning, Memory and Cognition
, 2008
"... Computational models of analogy have assumed that the strength of an inductive inference about the target is based directly on similarity of the analogs and in particular on shared higher order relations. In contrast, work in philosophy of science suggests that analogical inference is also guided by ..."
Abstract

Cited by 7 (1 self)
 Add to MetaCart
Computational models of analogy have assumed that the strength of an inductive inference about the target is based directly on similarity of the analogs and in particular on shared higher order relations. In contrast, work in philosophy of science suggests that analogical inference is also guided by causal models of the source and target. In 3 experiments, the authors explored the possibility that people may use causal models to assess the strength of analogical inferences. Experiments 1–2 showed that reducing analogical overlap by eliminating a shared causal relation (a preventive cause present in the source) from the target increased inductive strength even though it decreased similarity of the analogs. These findings were extended in Experiment 3 to crossdomain analogical inferences based on correspondences between higher order causal relations. Analogical inference appears to be mediated by building and then running a causal model. The implications of the present findings for theories of both analogy and causal inference are discussed.
Detecting the Direction of Causal Time Series
"... We propose a method that detects the true direction of time series, by fitting an autoregressive moving average model to the data. Whenever the noise is independent of the previous samples for one ordering of the observations, but dependent for the opposite ordering, we infer the former direction to ..."
Abstract

Cited by 7 (2 self)
 Add to MetaCart
We propose a method that detects the true direction of time series, by fitting an autoregressive moving average model to the data. Whenever the noise is independent of the previous samples for one ordering of the observations, but dependent for the opposite ordering, we infer the former direction to be the true one. We prove that our method works in the population case as long as the noise of the process is not normally distributed (for the latter case, the direction is not identifiable). A new and important implication of our result is that it confirms a fundamental conjecture in causal reasoning — if after regression the noise is independent of signal for one direction and dependent for the other, then the former represents the true causal direction — in the case of time series. We test our approach on two types of data: simulated data sets conforming to our modeling assumptions, and real world EEG time series. Our method makes a decision for a significant fraction of both data sets, and these decisions are mostly correct. For real world data, our approach outperforms alternative solutions to the problem of time direction recovery. 1.
Beware of the DAG!
 NIPS 2008 WORKSHOP ON CAUSALITY
, 2008
"... Directed acyclic graph (DAG) models are popular tools for describing causal relationships and for guiding attempts to learn them from data. In particular, they appear to supply a means of extracting causal conclusions from probabilistic conditional independence properties inferred from purely observ ..."
Abstract

Cited by 7 (0 self)
 Add to MetaCart
Directed acyclic graph (DAG) models are popular tools for describing causal relationships and for guiding attempts to learn them from data. In particular, they appear to supply a means of extracting causal conclusions from probabilistic conditional independence properties inferred from purely observational data. I take a critical look at this enterprise, and suggest that it is in need of more, and more explicit, methodological and philosophical justification than it typically receives. In particular, I argue for the value of a clean separation between formal causal language and intuitive causal assumptions.