Pedro L. Cobos

Mechanisms of Predictive and Diagnostic Causal Induction

In predictive causal inference, people reason from causes to effects, whereas in diagnostic inference, they reason from effects to causes. Independently of the causal structure of the events, the temporal structure of the information provided to a reasoner may vary (e.g., multiple events followed by a single event vs. a single event followed by multiple events). The authors report 5 experiments in which causal structure and temporal information were varied independently. Inferences were influenced by temporal structure but not by causal structure. The results are relevant to the evaluation of 2 current accounts of causal induction, the Rescorla-Wagner (R. A. Rescorla & A. R. Wagner, 1972) and causal model theories (M. R. Waldmann & K. J. Holyoak, 1992).

Associative and causal reasoning accounts of causal induction : Symmetries and asymmetries in predictive and diagnostic inferences

Associative and causal reasoning accounts are probably the two most influential types of accounts of causal reasoning processes. Only causal reasoning accounts predict certain asymmetries between predictive (i.e., reasoning from causes to effects) and diagnostic (i.e., reasoning from effects to causes) inferences regarding cue-interaction phenomena (e.g., the overshadowing effect). In the experiments reported here, we attempted to delimit the conditions under which these asymmetries occur. The results show that unless participants perceived the relevance of causal information to solving the task, predictive and diagnostic inferences were symmetrical. Specifically, Experiments 1A and 1B showed that implicitly stressing the relevance of causal information by having participants review the instructions favored the presence of asymmetries between predictive and diagnostic situations. In addition, Experiment 2 showed that explicitly stressing the relevance of causal information by stating the importance of the causal role of events after the instructions were given also favored the asymmetry.

Interference between cues of the same outcome depends on the causal interpretation of the events

In an interference-between-cues design, the expression of a learned Cue A ↠ Outcome 1 association has been shown to be impaired if another cue, B, is separately paired with the same outcome in a second learning phase. In the present study, we assessed whether this interference effect is mediated by participants’ previous causal knowledge. This was achieved by having participants learn in a diagnostic situation in Experiment 1a, and then by manipulating the causal order of the learning task in Experiments 1b and 2. If participants use their previous causal knowledge during the learning process, interference should only be observed in the diagnostic situation because only there we have a common cause (Outcome 1) of two disjoint effects, namely cues A and B. Consistent with this prediction, interference between cues was only found in Experiment 1a and in the diagnostic conditions of Experiments 1b and 2.

Does the type of judgement required modulate cue competition

According to the comparator process hypothesis (Matute, Arcediano, & Miller, 1996), cue competition in the learning of between-events relationships arises if the judgement required involves a comparison between the probability of the outcome given the target cue and the probability of the outcome given the competing cue. Alternatively, other associative accounts (the Rescorla-Wagner model: Rescorla &Wagner, 1972) conceive cue competition as a learning deficit affecting the target cue-outcome association. Consequently, the comparator process hypothesis predicts that cue competition occurs in inference judgements but not in contiguity ones, for only the first type of judgement implicitly involves such a comparison. On the other hand, the Rescorla-Wagner model predicts cue competition in both inference and contiguity judgements, because it establishes no relevant role for the type of judgement in producing cue competition. In Experiments 1 and 2 we manipulated the relative validity of cues and the type of question (inference vs. contiguity) in a predictive learning task. In both experiments we found a cue competition effect, but no interaction between the relative validity of cues and the type of question, suggesting that the Rescorla-Wagner theory suffices to explain cue competition.

An associative framework for probability judgment: An application to biases

Three experiments show that understanding of biases in probability judgment can be improved by extending the application of the associative-learning framework. In Experiment 1, the authors used M. A. Gluck and G. H. Bowers (1988a) diagnostic-learning task to replicate apparent base-rate neglect and to induce the conjunction fallacy in a later judgment phase as a by-product of the conversion bias. In Experiment 2, the authors found stronger evidence of the conversion bias with the same learning task. In Experiment 3, the authors changed the diagnostic-learning task to induce some conjunction fallacies that were not based on the conversion bias. The authors show that the conjunction fallacies obtained in Experiment 3 can be explained by adding an averaging component to M. A. Gluck and G. H. Bowers model.

Associative Repetition Priming as a Measure of Human Contingency Learning: Evidence of Forward and Backward Blocking

Associative theories have been widely used to explain human contingency learning. Standard experimental procedures in the field have requested verbal judgments as a measure of the cue-outcome relationships learned. According to these theories, knowledge retrieval is based on spreading activation processes. However, verbal judgments may allow or even promote the engagement of high-order processes that may hinder the interpretation of verbal judgments as the output of automatic retrieval processes like those posited. However, previous studies on human associative memory have shown that priming tests, under the right conditions, can minimize the engagement of high-order processes and serve as a measure of low-level automatic retrieval processes. Thus, a new human contingency learning task that incorporates a recognition priming test was developed and tested here. The results showed that, as predicted by associative theories, repetition priming was found after training. In addition, the results showed that relevant learning phenomena such as forward and backward blocking could also be detected using this test. Finally, training based on instructions did not modulate the priming effect. The relevance of these findings for theories of human contingency learning and priming is discussed.

Interference between cues of the same outcome in a non-causally framed scenario

Retroactive interference between cues of the same outcome (i.e., IbC) occurs when the behavioral expression of an association between a cue and an outcome (e.g., A-->O1) is reduced due to the later acquisition of an association between a different cue and the same outcome (e.g., B-->O1). Though this interference effect has been traditionally explained within an associative framework, there is recent evidence showing that IbC effect may be better understood in terms of the operation of higher order causal reasoning processes. The results from Experiments 1 and 2 showed an IbC effect in a learning task within a game scenario suggesting non-causal relationships between events. Thus, these results showed that IbC may have a diverse origin, one of them being of an associative nature.

Interference Between Outcomes, Spontaneous Recovery, and Context Effects as Measured by a Cued Response Reaction Time Task: Evidence for Associative Retrieval Models

The most common associative explanation of interference is based on a retrieval failure. Retrieval, in turn, is considered as the result of an associative activation mechanism that is thought to be fast and automatic. However, up-to-date, there is no evidence of interference based on dependent measures specifically related to this kind of low level processes. The objective of the present study was to test whether interference phenomena can be observed by using a cued response task designed to detect low level retrieval processes. Experiment 1 evaluated whether the cued response task served to show a priming effect. Such effect allowed us to interpret the results found in the remaining experiments of the series. Experiment 2 aimed to find the interference effect by using the cued response task. Experiments 3 and 4 were conducted to assess whether spontaneous recovery and context-change effects could also be observed. The results showed that interference and recovery from interference phenomena can be attributable to fast retrieval processes, which is consistent with associative accounts of interference.

Dependent Measure and Time Constraints Modulate the Competition Between Conflicting Feature-Based and Rule-Based Generalization Processes.

In our study, we tested the hypothesis that feature-based and rule-based generalization involve different types of processes that may affect each other producing different results depending on time constraints and on how generalization is measured. For this purpose, participants in our experiments learned cue–outcome relationships that followed the opposites rule: Single cues that signaled the same outcome (e.g., A-1/B-1) predicted the opposite outcome when presented in compound (e.g., AB-2). Some cues were only presented in compound during training (e.g., EF-1) to see if at test participants tended to generalize according to rule-based (i.e., E-2/F-2) or according to feature-based generalization (i.e., E-1/F-1). The generalization test used 2 different tasks: a predictive judgment task, and a cued-response priming task. In Experiment 1, participants’ verbal ratings were consistent with rule-based generalization. However, participants’ reaction times (RTs) in the cued-response priming task were consistent with feature-based generalization. Experiment 2 replicated the results from Experiment 1, and it also provided evidence consistent with feature-based or rule-based generalization depending on whether a short stimulus onset asynchrony (SOA; 200 ms) or a long SOA (1300 ms), respectively, was used in the priming task. Our results are interpreted as supporting the idea that feature-based generalization process relies on fast, associative processes, whereas rule-based generalization is slow and depends on executive control resources. The latter generalization process would inhibit the former when enough time and resources are available. Otherwise, feature-based generalization would take control of responses.

The role of outcome inhibition in interference between outcomes: A contingency-learning analogue of retrieval-induced forgetting

Current associative theories of contingency learning assume that inhibitory learning plays a part in the interference between outcomes. However, it is unclear whether this inhibitory learning results in the inhibition of the outcome representation or whether it simply counteracts previous excitatory learning so that the outcome representation is neither activated nor inhibited. Additionally, these models tend to conceptualize inhibition as a relatively transient and cue-dependent state. However, research on retrieval-induced forgetting suggests that the inhibition of representations is a real process that can be relatively independent of the retrieval cue used to access the inhibited information. Consistent with this alternative view, we found that interference between outcomes reduces the retrievability of the target outcome even when the outcome is associated with a novel (non-inhibitory) cue. This result has important theoretical implications for associative models of interference and shows that the empirical facts and theories developed in studies of retrieval-induced forgetting might be relevant in contingency learning and vice versa.