An Empirical Analysis of Interspersal Research: Evidence, Implications, and Applications of the Discrete Task Completion Hypothesis

Because assignment completion is often reinforced, researchers have posited that when students work on assignments with many discrete tasks (e.g., 20 mathematics problems), that each completed discrete task may be a conditioned reinforcer (e.g., Skinner et al., 1999). If the discrete task completion hypothesis is accurate, then relative task completion rates should influence choice behavior in the same manner as relative rates of reinforcement. In the current study, previous interspersal research was combined across experiments and regression analysis revealed a linear relationship between relative problem completion rates (RPCR) and choice in accordance with the matching law (Herrnstein, 1961, 1970). These results support the discrete task completion hypothesis and suggest that interspersing additional brief tasks enhances interval schedules of reinforcement. Theoretical and applied implications of the current study and the discrete problem completion hypothesis are discussed and directions for future research are provided.     

A Test by Any Other Name: P Values,Bayes Factors,and Statistical Inference

Procedures used for statistical inference are receiving increased scrutiny as the scientific community studies the factors associated with insuring reproducible research. This note addresses recent negative attention directed at p values, the relationship of confidence intervals and tests, and the role of Bayesian inference and Bayes factors, with an eye toward better understanding these different strategies for statistical inference. We argue that researchers and data analysts too often resort to binary decisions (e.g., whether to reject or accept the null hypothesis) in settings where this may not be required.     

Interference Effects in the Conservation of Weight

On the assumption that the ability to overcome the effects of interference between the physical properties of an object is a basic component in the acquisition of conservation, we hypothesized that children would tend to negate conservation not only when the form of an object is altered but also when, without deforming the object, one of its properties (e.g., color or temperature) is altered; when variations (e.g., movement or orientation) are introduced into the concrete situation in which weight is exerted; or when other spatial properties (e.g., volume or surface) are made to interact with weight. The results indicate that children up to 8 years of age may have difficulty accepting the conservation of weight even when a transformation does not deform the object and that children up to 13 years may accept the conservation of weight but may find it difficult to explain why an object appears heavier in those instances where weight has to be coordinated with another spatial property. The theoretical implications of these results are discussed.     

Interference effects in the conservation of weight

On the assumption that the ability to overcome the effects of interference between the physical properties of an object is a basic component in the acquisition of conservation, we hypothesized that children would tend to negate conservation not only when the form of an object is altered but also when, without deforming the object, one of its properties (e.g., color or temperature) is altered; when variations (e.g., movement or orientation) are introduced into the concrete situation in which weight is exerted; or when other spatial properties (e.g., volume or surface) are made to interact with weight. The results indicate that children up to 8 years of age may have difficulty accepting the conservation of weight even when a transformation does not deform the object and that children up to 13 years may accept the conservation of weight but may find it difficult to explain why an object appears heavier in those instances where weight has to be coordinated with another spatial property. The theoretical implications of these results are discussed.     

Accepting the null hypothesis

This article concerns acceptance of the null hypothesis that one variable has no effect on another. Despite frequent opinions to the contrary, this null hypothesis can be correct in some situations. Appropriate criteria for accepting the null hypothesis are (1) that the null hypothesis is possible; (2) that the results are consistent with the null hypothesis; and (3) that the experiment was a good effort to find an effect. These criteria are consistent with the meta-rules for psychology. The good-effort criterion is subjective, which is somewhat undesirable, but the alternative—never accepting the null hypothesis—is neither desirable nor practical.     

Conscious, but not unconscious, logo priming of brands and related words

This study assessed whether real-life stimulus material can elicit conscious and unconscious priming. A typical masked priming paradigm was used, with brand logo primes. We used a rigorous method to assess participants' awareness of the subliminal information. Our results show that shortly presented and masked brand logos (e.g., logo of McDonald's) have the power to prime their brand names (e.g., "McDonald's") and, remarkably, words associated to the brand (e.g., "hamburger"). However, this only occurred when the logos could be categorized clearly above the consciousness threshold. Once the primes were presented close to the consciousness threshold, no subliminal influences on behavior were observed.     

The effects of diffuse and distinct affect

In a series of suboptimal priming studies, it was shown that both affective and nonaffective reactions to a stimulus may occur without awareness. Moreover, it was demonstrated that affective information is detected earlier than nonaffective information. Therefore, early reactions to an affect-laden stimulus (e.g., a smiling man) are cognitively unappraised and thus diffuse (e.g., "positive"), whereas later affective reactions can be more specific and distinct (e.g., "a smiling man"). Through variations of prime exposure (extremely short, moderately short) the impact of early diffuse and late distinct affect on judgment was investigated. Findings show that distinctness (and prime-target similarity) is an essential determinant of whether the effect of affect is null, assimilation, or contrast. Furthermore, whether affect priming activates diffuse or distinct reactions is a matter of a fraction of seconds.     

Implicit proactive interference, age, and automatic versus controlled retrieval strategies

We assessed the extent to which implicit proactive interference results from automatic versus controlled retrieval among younger and older adults. During a study phase, targets (e.g., "ALLERGY") either were or were not preceded by nontarget competitors (e.g., "ANALOGY"). After a filled interval, the participants were asked to complete word fragments, some of which cued studied words (e.g., "A_L_ _GY"). Retrieval strategies were identified by the difference in response speed between a phase containing fragments that cued only new words and a phase that included a mix of fragments cuing old and new words. Previous results were replicated: Proactive interference was found in implicit memory, and the negative effects were greater for older than for younger adults. Novel findings demonstrate two retrieval processes that contribute to interference: an automatic one that is age invariant and a controlled process that can reduce the magnitude of the automatic interference effects. The controlled process, however, is used effectively only by younger adults. This pattern of findings potentially explains age differences in susceptibility to proactive interference.     

A tutorial on a practical Bayesian alternative to null-hypothesis significance testing

Null-hypothesis significance testing remains the standard inferential tool in cognitive science despite its serious disadvantages. Primary among these is the fact that the resulting probability value does not tell the researcher what he or she usually wants to know: How probable is a hypothesis, given the obtained data? Inspired by developments presented by Wagenmakers (Psychonomic Bulletin &; Review, 14, 779–804, 2007), I provide a tutorial on a Bayesian model selection approach that requires only a simple transformation of sum-of-squares values generated by the standard analysis of variance. This approach generates a graded level of evidence regarding which model (e.g., effect absent [null hypothesis] vs. effect present [alternative hypothesis]) is more strongly supported by the data. This method also obviates admonitions never to speak of accepting the null hypothesis. An Excel worksheet for computing the Bayesian analysis is provided as supplemental material.     

Using reinforcement learning to understand the emergence of "intelligent" eye-movement behavior during reading

The eye movements of skilled readers are typically very regular (K. Rayner, 1998). This regularity may arise as a result of the perceptual, cognitive, and motor limitations of the reader (e.g., limited visual acuity) and the inherent constraints of the task (e.g., identifying the words in their correct order). To examine this hypothesis, reinforcement learning was used to allow an artificial "agent" to learn to move its eyes to read as efficiently as possible. The resulting patterns of simulated eye movements resembled those of skilled readers and suggest that important aspects of eye-movement behavior might emerge as a consequence of satisfying the constraints that are imposed on readers. These results also suggest novel interpretations of some contentious empirical results, such as the fixation duration costs associated with word skipping (R. Kliegl & R. Engbert, 2005), and theoretical assumptions, for example the familiarity check in the E-Z Reader model of eye-movement control (E. D. Reichle, A. Pollatsek, D. L. Fisher, & K. Rayner, 1998).     

On the Anglocentricities of current reading research and practice: the perils of overreliance on an "outlier" orthography

In this critique of current reading research and practice, the author contends that the extreme ambiguity of English spelling-sound correspondence has confined reading science to an insular, Anglocentric research agenda addressing theoretical and applied issues with limited relevance for a universal science of reading. The unique problems posed by this "outlier" orthography, the author argues, have focused disproportionate attention on oral reading accuracy at the expense of silent reading, meaning access, and fluency, and have significantly distorted theorizing with regard to many issues-including phonological awareness, early reading instruction, the architecture of stage models of reading development, the definition and remediation of reading disability, and the role of lexical-semantic and supralexical information in word recognition. The dominant theoretical paradigm in contemporary (word) reading research--the Coltheart/Baron dual-route model (see, e.g., J. Baron, 1977; M. Coltheart, 1978) and, in large measure, its connectionist rivals--arose largely in response to English spelling-sound obtuseness. The model accounts for a range of English-language findings, but it is ill-equipped to serve the interests of a universal science of reading chiefly because it overlooks a fundamental unfamiliar-to-familiar/novice-to-expert dualism applicable to all words and readers in all orthographies.     

Individual differences among children in spelling and reading styles

Previous studies have found differences among children in their relative reliance on spelling-sound rules and word-specific associations in reading words. Children at one end of the continuum ("Phoenicians") rely heavily on spelling-sound rules; children at the other end ("Chinese") are more likely to use specific associations. This study found evidence for a Phoenician-Chinese continuum in spelling as well as in reading. Ability to spell nonsense word (e.g., "prunt") correlated more highly with ability to spell regular words (e.g., "grunt") than with ability to spell exception words (e.g., "front"). Children who were skilled at rules tended to overgeneralize them to exception words. In addition, a measure of rule use in spelling correlated with measures of rule use in reading.     

Being forward not backward: lexical limits to masked priming

This study investigated whether masked priming is mediated by existing memory representations by determining whether nonwords targets would show repetition priming. To avoid the potential confound that nonword repetition priming would be obscured by a familiarity response bias, the standard lexical decision and naming tasks were modified to make targets unfamiliar. Participants were required to read a target string from right to left (i.e., "ECAF" should be read as "FACE") and then make a response. To examine if priming was based on lexical representations, repetition primes consisted of words when read forwards or backwards (e.g., "face", "ecaf") and nonwords (e.g., "pame", "emap"). Forward and backward primes were used to test if task instruction affected prime encoding. The lexical decision and naming tasks showed the same pattern of results: priming only occurred for forward primes with word targets (e.g., "face-ECAF"). Additional experiments to test if response priming affected the LDT indicated that the lexical status of the prime per se did not affect target responses. These results showed that the encoding of masked primes was unaffected by the novel task instruction and support the view that masked priming is due to the automatic triggering of pre-established computational processes based on stored information.     

Subliminal perception and its cognates: theory, indeterminacy, and time

Unconscious processes, by whatever name they may be known (e.g., "subliminal," "implicit"), are invariably operationalized by the dissociation paradigm, any situation involving the dissociation between two indicators (or sets of indicators), one of availability (epsilon) and the other, of accessibility (alpha), such that, epsilon>alpha. Subliminal perception has been traditionally defined by a special case of the dissociation paradigm in which availability exceeds accessibility when accessibility is null (epsilon>alpha/alpha=0). Construct validity issues bedevil all dissociation paradigms since it is not clear what might constitute appropriate indicators that, moreover, are pure and exhaustive. Semantic and theoretic drifts in the recent literature--e.g., the confusion of different versions of the dissociation paradigm, the equation of conscious-unconscious with direct-indirect tests, and the foisting of the criterion of qualitative differences--have tended to undermine emerging theoretic parsimony. On the other hand, a crucial factor has been left out of theory development: time. Both epsilon and alpha can rise and fall over time, often asynchronously, and so dissociations may wax and wane and, even, reverse over time. Some laboratory evidence suggests that accessibility measures (e.g., d'), as they approach chance, may actually dip below chance (subchance perception). If so, d'=0 (the chance-limen or objective threshold), could be an averaging artifact of positive and negative d's. Conscious accessibility is not either-or but more or less, and variable over time.     

Partner effects in relationship research: Conceptual issues,analytic difficulties,and illustrations

This article discusses the conceptual meaning of partner effects, which occur when one person is affected by the behavior or characteristics of his or her partner. We show that partner effects can be used to validate the presence of a relationship and can elaborate the particular nature of that relationship. We discuss possible moderation of partner effects and show that many theoretical variables in relationship research (e.g., similarity) can be viewed as the interactions of partner effects with other variables. We present three extended examples that illustrate the importance of partner effects.     

A new look at the consequences of attitude certainty: the amplification hypothesis

It is well established that increasing attitude certainty makes attitudes more resistant to attack and more predictive of behavior. This finding has been interpreted as indicating that attitude certainty crystallizes attitudes, making them more durable and impactful. The current research challenges this crystallization hypothesis and proposes an amplification hypothesis, which suggests that instead of invariably strengthening an attitude, attitude certainty amplifies the dominant effect of the attitude on thought, judgment, and behavior. In 3 experiments, the authors test these competing hypotheses by comparing the effects of attitude certainty manipulations on univalent versus ambivalent attitudes. Across experiments, it is demonstrated that increasing attitude certainty strengthens attitudes (e.g., increases their resistance to persuasion) when attitudes are univalent but weakens attitudes (e.g., decreases their resistance to persuasion) when attitudes are ambivalent. These results are consistent with the amplification hypothesis.     

Quasi-Realism, Negation and the Frege-Geach Problem

Every expressivist theory of moral language requires a solution to the Frege-Geach problem, i.e., the problem of explaining how moral sentences retain their meaning in unasserted (e.g., conditional and disjunctive) contexts. An essential part of Blackburn's ' quasi -realist project', i.e., the project of showing how we can earn the right to treat moral sentences as if they have ordinary truth-conditions, is to provide a sophisticated solution. I show, however, that simple negated contexts provide a fundamental difficulty, since accepting the negation of a sentence is easily confused with merely refusing to accept that sentence. I argue that Blackburn's model-set semantics for his 'Hooray!' and 'Boo!' operators requires logical apparatus to which he is not entitled. I consider various modifications, but show that they do not succeed.
email : n.unwin@bolton.ac.uk     

Conditions affecting the revelation effect for autobiographical memory

In four experiments involving 184 participants, people rated their confidence that particular events had happened in their childhood (e.g., "Broke a window playing ball"). If participants had to unscramble a key word in a phrase just before rating it (e.g., "Broke a nwidwo [window] playing ball"), confidence ratings increased-the revelation effect. However, the pattern of revelation effects depended on the particular way in which participants processed key words (e.g., visualizing vs. counting vowels in the word window) approximately 10 min prior to rating life events that contained those words. Prior exposure to key words never in itself directly affected confidence ratings. These results demonstrate that one can manipulate the revelation effect by altering the processing that participants perform on words prior to unscrambling them. These results also pose difficulties for many accounts of the revelation effect. The major puzzle posed by our present findings is that unscrambling key words increases confidence that an event has happened in childhood, whereas prior exposure to these words does not.