The negated conditional: a litmus test for the suppositional conditional?

Under the suppositional account of conditionals, when people think about a conditional assertion, "if p then q," they engage in a mental simulation in which they imagine p holds and evaluate the probability that q holds under this supposition. One implication of this account is that belief in a conditional equates to conditional probability [P(q/p)]. In this paper, the authors examine a further implication of this analysis with respect to the wide-scope negation of conditional assertions, "it is not the case that if p then q." Under the suppositional account, nothing categorically follows from the negation of a conditional, other than a second conditional, "if p then not-q." In contrast, according to the mental model theory, a negated conditional is consistent only with the determinate state of affairs, p and not-q. In 4 experiments, the authors compare the contrasting predictions that arise from each of these accounts. The findings are consistent with the suppositional theory but are incongruent with the mental model theory of conditionals.     

The Rorschach: does it have a future?

Recent evidence suggests that in spite of an increasingly critical attitude by many clinicians towards the use of projective techniques, the use of these techniques has not faltered over the years. Insofar as the Rorschach continues to be the most popular projective instrument, its scientific status is critically examined in the present paper. The problems inherent in examining an instrument which has engendered a number of quite distinct scoring systems are noted, and the conclusion is advanced that notwithstanding such problems there seems little likelihood that the Rorschach will experience any significantly diminished popularity in the future.     

Is there a logic of incoherence?

What should we do when we discover that our assessment of probabilities is incoherent? I explore the hypothesis that there is a logic of incoherence—a set of universally valid rules that specify how incoherent probability assessments are to be repaired. I examine a pair of candidate‐rules of incoherence logic that have been employed in philosophical reconstructions of scientific arguments. Despite their intuitive plausibility, both rules turn out to be invalid. There are presently no viable candidate‐rules for an incoherence logic on the table. Other ways of dealing with incoherence are surveyed, and found either to be unsatisfactory or to rely on a logic of incoherence in the end. The resolution of these antagonistic conclusions is left to future researchers.     

Hierarchical categorization by bilingual Latino children: does a basic-level bias exist?

Research has shown that children classify most easily at the basic level where objects in the same category look similar enough to each other to be grouped together but are distinct enough from objects in other categories to be discriminated (e.g., animal/bird/duck). In this article, the authors report on 2 experiments they conducted to determine whether children maintain this basic category bias when the perceptual similarity of stimuli at different hierarchical levels is equalized. Pictures within and across 3 hierarchical levels were made perceptually equivalent and shown to 71 Latino children who were bilingual in Spanish and English. In Experiment 1, the pictures used as exemplars could be categorized on any of the 3 hierarchical levels. In Experiment 2, example pictures unambiguously defined the level of categorization that would be accurate, and linguistic cues were given that might assist in the selection of the correct category. In both experiments, the children sorted pictures from all 3 levels equally well, but they found it harder to justify their sorting of superordinate pictures. English competence predicted sorting on the more ambiguous sorting task in Experiment 1; and English competence predicted verbal justifications in both experiments, even though the experiments were conducted in Spanish. Competence in Spanish or English was an equally good predictor of sorting in the better defined sorting task in Experiment 2. These findings indicate that a superordinate level deficiency remains after perceptual differences are eliminated and that the deficiency is cognitive in nature. Differences in the performances of children who differed in bilingualism support the hypothesis that a threshold of proficiency in both languages is an important determinant of the effect of bilingualism on categorization.     

What makes us believe a conditional? The roles of covariation and causality

Two experiments were conducted to investigate the roles of covariation and of causality in people's readiness to believe a conditional. The experiments used a probabilistic truth-table task (Oberauer & Wilhelm, 2003 Oberauer, K. and Wilhelm, O. 2003. The meaning(s) of conditionals: Conditional probabilities, mental models, and personal utilities. Journal of Experimental Psychology: Learning, Memory & Cognition, 29: 680–693. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) in which people estimated the probability of a conditional given information about the frequency distribution of truth-table cases. For one group of people, belief in the conditional was determined by the conditional probability of the consequent, given the antecedent, whereas for another group it depended on the probability of the conjunction of antecedent and consequent. There was little evidence that covariation, expressed as the probabilistic contrast or as the pCI rule (White, 2003 White, P. A. 2003. Making causal judgements from the proportion of confirming instances: The pCI rule. Journal of Experimental Psychology: Learning, Memory, and Cognition, 29: 710–727.  [Google Scholar]), influences belief in the conditional. The explicit presence of a causal link between antecedent and consequent in a context story had a weak positive effect on belief in a conditional when the frequency distribution of relevant cases was held constant.     

The effects of time and distance on accuracy of target-directed locomotion: does an accurate short-term memory for spatial location exist?

The present study was an attempt to replicate the findings of an influential set of experiments by Thomson (1980, 1983) in which he demonstrated a highly accurate but transitory short-term memory for target location during locomotion. No evidence of Thomson's rapidly decaying 8 s short-term memory was found in either of the two experiments presented here. The distance to the target, not the elapsed time, was found to be the major variable affecting the accuracy of walks made without the benefit of visual feedback; as target distance increased so did locomotor error. Increasing the elapsed time to more than 8 s between viewing the target and reaching the vicinity of the target had no effect on the accuracy of walks made with eyes closed. When the elapsed time was greater than 30 s, however, performance began to deteriorate. These results suggest, in sharp contrast to Thomson's experiments, that short-term memory for target location decays rather slowly during locomotion. In this regard, short-term memory in locomotor tasks appears to be little different from the kinds of short-term memory associated with other motor acts.     

The immoral gene: Does it really exist?

Over the last years several European patents were opposed for protecting technology violating the morality requirement under Article 53(a) EPC. Attempts have been made by the Appeal Boards of the European Patent Office (EPO), as well as by amendments introduced into the Implementing Regulations of the European Patent Convention (EPC), to address this sensitive patentability requirement more precisely. The most recent hot topic coming up in this context is the patentability of stem cells. It is to be expected that this discussion will still go on in the field of biotechnological inventions for the next several years. An earlier version of this paper was presented at an international conference, “The Ethics of Intellectual Property Rights and Patents,” held in Warsaw, Poland on 23–24 April, 2004.     

The irrelevant sound effect: does speech play a special role?

Memory for order is markedly impaired by the presence of irrelevant sound, even though participants are instructed to ignore the sound. Although a great deal of research has disclosed some features of the task and of the sound that augment or reduce the degree of interference, one important issue of the irrelevant sound effect not yet resolved is whether speech has a special status. This study revealed, within a design of adequate power, that the same physical stimulus (sine wave speech), whether perceived as speech or as nonspeech sound, produces similar degrees of disruption and is less disruptive of serial recall than natural speech. This outcome suggests that the acoustic constituents of sound rather than its source are most influential in determining the impact of irrelevant material.     

Potentiation in young infants: The origin of the prior knowledge effect?

In two experiments with 6-month-old infants, we found that prior learning of an operant task (remembered for 2 weeks) mediated new learning of a modeling event (remembered for only 1 day) and increased its recall. Infants first learned to associate lever pressing with moving a toy train housed in a large box. One or 2 weeks later, three target actions were modeled on a hand puppet while the train box (a retrieval cue) was in view. Merely retrieving the train memory strengthened it, and simultaneously pairing its retrieved memory with the modeled actions potentiated their learning and recall. When paired 1 week later, deferred imitation increased from 1 day to 4 weeks; when paired 2 weeks later, it increased from 1 day to 6 weeks. The striking parallels between potentiated learning in infants and the prior knowledge effect in adults suggests that the prior knowledge effect originates in early infancy.     

The origin of children's implanted false memories: Memory traces or compliance?

A longstanding question in false memory research is whether children's implanted false memories represent actual memory traces or merely result from compliance. The current study examined this question using a response latency based deception task. Forty-five 8-year-old children received narratives about a true (first day at school) and false event (hot air balloon ride). Across two interviews, 58/32% of the participants developed a partial/full false memory. Interestingly, these children also showed higher false recall on an unrelated DRM paradigm compared to children without a false memory. The crucial finding, however, was that the results of the deception task revealed that children with partial and full false memories were faster to confirm than to deny statements relating to the false event. This indicates that children's implanted false memories reflect actual memory traces, and are unlikely to be explained by mere compliance.     

Effects of accenting and regularity on the detection of temporal deviations: does regularity facilitate performance?

In an experiment on the effect of intensity accents on the perception of time intervals between tones, H. G. Tekman (2001) found that the regular placement of deviant time intervals in short sequences of tones reduced detection, especially if intensity accents marked the deviant time intervals. That was the opposite of what one would have expected on the basis of the dynamic attending theory of M. R. Jones (1976). The effect might have occurred because temporally deviant tones create cumulative onset shifts that affect all the subsequent tones. If the deviations were randomly placed, then they could follow each other in close succession and change the local tempo. In the present study, the changes of local tempo, which might have acted as a cue for the detection of temporal deviations in the random sequences, were eliminated by compensating for deviant time intervals with equal deviations in the opposite direction in the interval that followed. That change in the stimuli eliminated the negative main effect of regularity, and the accenting interacted with regularity in favor of detection in the regular sequences. However, a simple advantage of regular over random sequences was not observed. The author discusses possible reasons for the lack of a facilitatory effect of regularity.     

Does a quarterlife crisis exist?

In this study, the authors examined quarterlife crisis, defined in the popular press as an identity crisis that leaves recent college graduates depressed, anxious, and full of doubt. To determine if a unique crisis exists, 4 groups of young adults (recent high school [n = 23] and college [n = 117] graduates in the workforce, present undergraduate [n = 75], and graduate [n = 57] students) completed self-report measures assessing identity development, future time perspective, social support, coping, depression, anxiety, and job and life satisfaction. No support was found for a quarterlife crisis among these 4 groups. Working high school graduates displayed the highest anxiety, followed by present undergraduates. Depression was predicted by family support and identity commitment. Job satisfaction was associated with income and support from friends. Life satisfaction was associated with income, social support from friends and family, and identity commitment.     

The logic of Simpson’s paradox

There are three distinct questions associated with Simpson’s paradox. (i) Why or in what sense is Simpson’s paradox a paradox? (ii) What is the proper analysis of the paradox? (iii) How one should proceed when confronted with a typical case of the paradox? We propose a “formal” answer to the first two questions which, among other things, includes deductive proofs for important theorems regarding Simpson’s paradox. Our account contrasts sharply with Pearl’s causal (and questionable) account of the first two questions. We argue that the “how to proceed question?” does not have a unique response, and that it depends on the context of the problem. We evaluate an objection to our account by comparing ours with Blyth’s account of the paradox. Our research on the paradox suggests that the “how to proceed question” needs to be divorced from what makes Simpson’s paradox “paradoxical.”     

The learning of two similar complex movement sequences: does practice insulate a sequence from interference?

Panzer et al. [Panzer, S., Wilde, H., & Shea, C. H. (2006). The learning of two similar complex movement sequences: Proactive and retroactive effects on learning. Journal of Motor Behavior, 38, 60-70] found evidence to indicate that the memory state(s) underpinning the production of a movement sequence that was practiced for one day was essentially "overwritten" when another similar sequence was subsequently practiced on the next day. An interference paradigm was used to determine if additional practice on the first sequence would insulate it from retroactive interference arising from learning a new similar sequence. Participants produced the sequences by moving a lever with their right arm/hand to sequentially presented target locations. The experimental group practiced one 16-element movement sequence (S1) for two consecutive days. A second 16-element sequence (S2) was practiced on Day 3. The sequence practiced on Day 3 was created by switching the positions of 2 of 16 elements in the sequence practiced on the first day. Control groups received either two days of practice on S1 or one day of practice on S2. Contrary to our earlier findings (Panzer, Wilde, & Shea, 2006) of strong retroactive interference when S1 was only practiced for one day, we found no evidence of retroactive interference when S1 was practiced for two days prior to the switch to S2 practice. Interestingly, but also contrary to our earlier findings, we found the learning of S2 was facilitated by the prior practice of S1. This proactive facilitation was observed in S2 acquisition and on the S2 retention test.     

What does being initiated severely into a group do? The role of rewards

Undergoing an admission process (an initiation) can induce exaggerated feelings about a group, but there is little research about the role of rewards. This study replicated Aronson and Mills’ (1959) experiment. Seventy participants underwent either a severe initiation or a mild initiation. After the initiation, about half the sample received an extrinsic reward for merely completing the task. The remaining half did not receive an extrinsic reward. This was to vary the amount of dissonance. Initiation severity and reward condition had significant, noncrossing interactions. A reward led to higher group identity than no reward, supporting Levine and Moreland's (1994) group socialization model. A severe initiation did not lead to more group identity than a mild initiation; therefore, Aronson and Mills’ findings were not replicated. Interestingly, a mild initiation followed by a reward led to more group identity than a severe initiation followed by a reward. Another unexpected finding was that the extrinsic reward made no difference to group identity if the initiation was severe. Effects on ratings of the discussion were nonsignificant. Future research needs to establish how new group members ponder the severity of the admission process during the cost–benefit calculation preceding their identification with a group.