The CLASSI-N Method for the Study of Sequential Processes

In many psychological research domains stimulus-response profiles are explained by conjecturing a sequential process in which some variables mediate between stimuli and responses. Charting sequential processes is often a complex task because (1) many possible mediating variables may exist, and (2) interindividual differences may occur in the relationship between these mediating variables and the response. Recently, Ceulemans and Van Mechelen (Psychometrika 73(1):107–124, 2008) addressed these challenges by developing the CLASSI model. A major drawback of CLASSI is that it requires information about the same set of stimuli for all participants (i.e., crossed data), whereas recently a number of data gathering techniques have been proposed in which the set of stimuli differs across participants, yielding nested data. Therefore we present the CLASSI-N model, which extends the CLASSI model to nested data. A simulated annealing algorithm is proposed. The results of a simulation study are discussed as well as an application to data concerning depression.     

Freely generated filters in free Boolean algebras

In this paper we will prove that ifF is a filter of a free Boolean algebra such that the minimal cardinality of the set of generators ofF is an uncountable regular cardinal or a singular cardinal with uncountable cofinality thenF is freely generated.Presented byPiotr Wojtylak     

The Simon effect for vertical S–R relations: changing the mechanism by randomly varying the S–R mapping rule?

Recent findings indicate that the shape of the effect function of the Simon effect--derived by analysing the response time distribution for corresponding and non-corresponding trials--differs depending on the task. Specifically, decreasing effect functions have been reported for horizontal and stable rather increasing effect functions have been obtained for vertical stimulus-response (S-R) relations. Furthermore, it has been assumed that these differences reflect distinct mechanisms underlying the Simon effect. However, in two studies decreasing effect functions were reported for the vertical dimension. In order to investigate these contradictory findings four experiments were conducted. Since both studies--in which a decreasing effect function was obtained--used a modified version of the Simon task, that is, randomly varying S-R mapping rules, the Simon effect for fixed and random S-R mapping rules was investigated using vertical (Experiments 1, 2, and 4) and horizontal (Experiment 3) S-R relations. The results indicate that randomly varying S-R mapping rules affect the shape of the effect function for vertical but not for horizontal S-R relations. It was concluded that these findings indicate that the alternation of S-R mapping rules changes the information processing for the vertical dimension in a way, that the same mechanism as for horizontal S-R relations occurs.     

Equivalence of human odometry by walk and run is indifferent to self-selected speed

Humans and other animals can measure distances nonvisually by legged locomotion. Experiments typically employ an outbound measure (M) and an inbound report (R) phase. Previous research has found distance reproduction to be maximally accurate, when gait symmetry and speed of M and R are of like kind: Successful human odometry manifests at the level of the M-R system. In the present work, M was an experimenter-set distance produced by a blindfolded participant using a primary gait (walk, run). R was always by walk. Fast and slow versions of walk and run were adopted by participants, such that when M was fast R was slow, and vice versa. Distance was underestimated when M was slower than R and overestimated when M was faster than R. However, the pattern of participant-adopted velocities indicated that it was the instructions, not the speed as such, that yielded the pattern of results. The results are interpretable through a dynamical perspective and indicate speed is an imperfection parameter acting on the attractors of the M-R system.     

Person, situation, and person-by-situation interaction components in person perception

The hypothesis that people store situation and person-by-situation interaction information as well as trait information about one another's behavior was tested by administering modified S-R Inventories of Anxiousness and Hostility to 54 male and 59 female undergraduates. Subjects rated the strength of affect that would be evoked by a series of situations in the two same-sex college students whom they knew best, the best-known opposite-sex person, a casually known same-sex person, and the “average college student.” Indices were constructed to measure the extent of (a) perceived average differences among people (traits), (b)perceived average differences over situations, and (c) perceived person-by-situation interaction. Analyses of variance showed that: (a) the ratings of the two best-known same-sex persons and the best-known opposite-sex person contained more interactive information than did the ratings of a casually known person and (b) females perceived more situational variability in the behavior of their own sex than did males. The amount of perceived person-by-situation interaction did not differ as a function of sex of rater or affect to be rated. It was concluded that the naive psychologist, like many professional psychologists, is an interactionist.     

Unconscious priming according to multiple S-R rules

The present study investigated if unconscious primes can be processed according to different stimulus-response (S-R) rules simultaneously. Participants performed two different S-R rules, such as judging a digit as smaller or larger than five and judging a letter as vowel or consonant. These S-R rules were administered in random order and announced by a previously presented cue. Each target stimulus was preceded by subliminal primes which afforded a different or an identical response according to either the currently irrelevant or currently relevant S-R rule. In three experiments, we consistently found priming effects according to currently irrelevant S-R rules, even when primes for the relevant and irrelevant S-R rules were presented simultaneously. Thus, unconscious stimuli have the power to activate responses according to currently required and currently not required S-R rules concurrently. The results are in line with response activation accounts of subliminal priming and suggest that at least two routes may gain access on response processes simultaneously.     

Identifying the situational triggers underlying avoidance of communication situations and individual differences therein

People are actively involved in the selection and avoidance of the situations they face during everyday life. Moreover, such selection/avoidance behavior is subject to sizeable individual differences. Yet, to a large extent this phenomenon has been underinvestigated, and a full understanding of selection/avoidance remains lacking. In the present paper, we take a first step to a more in-depth understanding of situation avoidance, which is conceptualized in terms of individual profiles or signatures across situations. Two key objectives with regard to those signatures are being addressed, that is: (a) identifying the critical situational triggers that elicit avoidance behavior, and (b) identifying the most important individual differences in the link between these situational triggers and avoidance, along with their underlying process dynamics. To achieve these objectives, we performed an empirical study on avoidance of communication situations. This study revealed a set of person types that meaningfully differ in sensitivity to a few key situational features. These person types further appeared to differ from one another on several dispositional cognitive/affective forecast variables.     

Sticky rules: integration between abstract rules and specific actions

The authors manipulated repetitions and/or changes of abstract response rules and the specific stimulus- response (S-R) associations used under these rules. Experiments 1 and 2, assessing trial-to-trial priming effects, showed that repetition of complete S-R couplings produced only benefits when the rule also repeated (i.e., rule-S-R conjunctions) but costs when identical S-R couplings repeated while rules changed. In Experiments 3 and 4, the authors manipulated amount of experience with specific rule-S-R conjunctions and demonstrated integration between rules and S-R couplings in terms of cumulative practice effects. However, unlike short-term priming effects, cumulative practice supported generalization of experience with specific S-R couplings across rule boundaries (Experiment 4). Results are discussed in terms of constraints on models of hierarchical control and in terms of qualitatively different ways in which people profit from very recent experiences (i.e., all-or-none access to working memory representations) versus cumulative experience (i.e., similarity-based retrieval from long-term memory).     

Sheldon's physical-psychical typology revisited

In order to clarify some of the general findings in the literature with respect to relationships between body type and the personality dimension extraversion/introversion, typical experimental paradigms common to this field were replicated but using the first-order factors (from the R. B. Cattell, H. W. Eber, & M. M. Tatsuoka (1970, Handbook for the sixteen personality factor questionnaire, Windsor: N.F.E.R.) analysis) that load on this continuum rather than the continuum itself. Use was made of standard statistical procedures as well as discriminant analysis. The most noteworthy finding was that subjects were able to utilize the first-order factor structure for the continuum extraversion/introversion in a discriminating manner and to assign such factors in a fairly clear-cut way to three extreme body types. Personality appraisals of the mesomorphic body type and an ideal type (composed by the subjects) were shown to be virtually identical. The most positive extravert characteristics were assigned to the endomorph body build and the most positive introvert characteristics to the ectomorph. No differences in personality appraisals by male (n = 50) and female (n = 50) subjects with the exception of factor Q₂ by the ectomorphic body type were found. Both male and female subjects showed a preference for the (male) mesomorphic body type although significant differences between male and female subjects in the pattern of their distribution of preferences over the three body types were found. While the results confirm previous findings, they also extend them by the use of a first-order factor structure for the continuum extraversion/introversion and by the introduction of the explanatory concepts “extravert of affect” and “extravert of action.”     

Rapid-response versus free-time selection tasks using different logical connectives

When reasoning with conditional statements (i.e., if [not] p then [not] q), people tend to display matching bias: Options that match the entities named in the rule are selected even when logically inappropriate. Three different Wason selection tasks were administered under free-time and rapid-response formats. For the latter, individual cards were presented for one second, and required a response within a further one second. Previous research using these formats (Roberts & Newton, 2001) has shown that this increases matching bias, in line with the action of preconscious heuristic processes which direct attention towards relevant aspects of a problem, but whose action can be overturned if there is sufficient time to apply analytic reasoning processes. The selection tasks administered included a standard abstract conditional task, a disjunctive version (i.e., either [not] p or [not] q), and a conditional task in which the cards showed explicitly negated values. Both conditional tasks demonstrated matching bias, but under rapid-response presentation, matching bias only increased for the standard conditional and disjunctive tasks. Overall, the data support Evans’ (e.g., 2006) heuristic-analytic framework albeit with some caveats, and it is suggested that the broad question, of whether individual selection task formats show or do not show matching bias, requires more detailed investigation.     

Affective matching moderates S-R binding

We investigated the moderating influence of affective matching on S-R binding processes in a sequential priming study in which positive and negative nouns had to be categorised as referring to a person or to an object. Irrelevant positive and negative distractor words (adjectives) were integrated with responses into S-R episodes if they had the same valence as the target (affective match condition). In this case, repeating the prime distractor in the probe led to a retrieval of the prime response, which facilitated performance for response repetition sequences but had no effect on performance when responses changed between prime and probe. However, if target and distractor had different valences (affective mismatch condition), no interaction of distractor relation and response relation occurred, indicating that distractors were less likely to be associated with responses into event files during the prime trial episode. Findings reveal that affective mismatches are detected automatically and modulate a binding of irrelevant information with responses.     

Working memory involvement in dual-task performance: Evidence from the backward compatibility effect

In three experiments, the authors supported the hypothesis that parallel response activation seen in dual-task performance results from holding Task 2 rules in working memory (WM) while performing Task 1. To this end, the authors used the backward compatibility effect (BCE; quicker primary responses when the Task 2 response is compatible with codes of Task 1) as a marker for parallel response activation and manipulated WM load. Increasing the number of primary task rules from two to four did not modulate BCE, replicating Hommel and Eglau (2002), but a higher load condition, involving six primary task rules, reduced the BCE to nonsignificant levels. Experiment 3 further showed that WM is loaded by rules associating abstract stimulus categories to responses, and not by rules tt associate individual stimuli to responses (S-R rules).     

The Additive Factor Method: A differential diagnostic tool in hyperactivity and learning disability

The Additive Factor Method assumes that task performance is the sum of sequential and independent processes. We studied the duration of the central processes (memory search and decision) and the motor decision process in hyperactive and learning-disabled children under socalled divided attention and S-R compatibility conditions. It was found that the learning-disabled were impaired in memory search and decision processes whereas hyperactives were impaired in the motor decision process.The authors wish to thank L. Leertouwer for making the drawings.     

Optimization of sample size in controlled experiments: The CLAST rule

Sequential rules are explored in the context of null hypothesis significance testing. Several studies have demonstrated that the fixed-sample stopping rule, in which the sample size used by researchers is determined in advance, is less practical and less efficient than sequential stopping rules. It is proposed that a sequential stopping rule called CLAST (composite limited adaptive sequential test) is a superior variant of COAST (composite open adaptive sequential test), a sequential rule proposed by Frick (1998). Simulation studies are conducted to test the efficiency of the proposed rule in terms of sample size and power. Two statistical tests are used: the one-tailed t test of mean differences with two matched samples, and the chi-square independence test for twofold contingency tables. The results show that the CLAST rule is more efficient than the COAST rule and reflects more realistically the practice of experimental psychology researchers.     

Dynamic aspects of stimulus-response correspondence: evidence for two mechanisms involved in the Simon effect

It has been recently proposed that the time course of the Simon effect may vary across tasks, which might reflect different types of stimulus-response (S-R) transmissions (E. Wascher, U. Schatz, T. Kuder, & R. Verleger, 2001). The authors tested this notion in 4 experiments by comparing Simon effects evoked by horizontal and vertical S-R arrangements. The temporal properties of the effect, as well as lateralized readiness potential-difference waves, indicated a fast and transient influence of the horizontal, but a slow and sustained influence of the vertical spatial stimulus feature on performance. Additional evidence for this temporal dissociation was obtained in experiments that induced a shortening or lengthening of the mean response time. Thus, the data strongly indicate that there are 2 temporally dissociable mechanisms involved in generating the Simon effect for horizontal and vertical S-R relations.     

Co-occurrence of sequential and practice effects in the Simon task: Evidence for two independent mechanisms affecting response selection

The Simon effect refers to the observation that responses to a relevant stimulus dimension are faster and more accurate when the stimulus and response spatially correspond than when they do not, even though stimulus position is irrelevant. Recent findings have suggested that the Simon effect can be strongly modulated by prior practice with a spatially incompatible mapping and by correspondence sequence. Although practice is thought to influence conditional stimulus —response (S-R) processing, leaving response priming through the unconditional route unaffected, sequential effects are thought to represent trial-by-trial adaptations that selectively involve unconditional S —R processing. In the present study, we tested this assumption by assessing the effects of correspondence sequence both when the Simon task alone was performed and when it was preceded by a spatial compatibility task with either incompatible (Experiments 1-2) or compatible (Experiment 2) instructions. The observation that practice and correspondence sequence co-occur and exert additive effects strongly demonstrates that the two factors affect different processing routes.     

Automaticity without extensive training: The role of memory retrieval in implementation of task-defined rules

Although the concept of automaticity is closely associated with extensive rote training, previous studies have shown that task-defined stimulus-response (S-R) mappings can be implemented in parallel and involuntarily, without much training, as if they are automatically processed. An irrelevant task context may trigger a task-defined rule because the rule is actively maintained in working memory, resulting in erroneous implementation of that rule. However, the present study demonstrated that active maintenance of task rules is not necessary for their automatic implementation. Instead, the results are consistent with the memory view of automaticity, according to which task-defined S-R rules are implemented via automatic retrieval of S-R episodes.     

A feature-integration account of sequential effects in the Simon task

Recent studies have shown that the effects of irrelevant spatial stimulus-response (S-R) correspondence (i.e., the Simon effect) occur only after trials in which the stimulus and response locations corresponded. This has been attributed to the gating of irrelevant information or the suppression of an automatic S-R route after experiencing a noncorresponding trial—a challenge to the widespread assumption of direct, intentionally unmediated links between spatial stimulus and response codes. However, trial sequences in a Simon task are likely to produce effects of stimulus- and response-feature integration that may mimic the sequential dependencies of Simon effects. Four experiments confirmed that Simon effects are eliminated if the preceding trial involved a noncorresponding S-R pair. However, this was true even when the preceding response did not depend on the preceding stimulus or if the preceding trial required no response at all. These findings rule out gating/suppression accounts that attribute sequential dependencies to response selection difficulties. Moreover, they are consistent with a feature-integration approach and demonstrate that accounting for the sequential dependencies of Simon effects does not require the assumption of information gating or response suppression.     

Is there a direct relation between the development of vocabulary and grammar?

Previous studies of individual differences have revealed strong correlations between children's vocabulary and grammatical abilities, and these data have been used to support theoretical accounts positing direct developmental relations between these two areas of language. However, between‐person differences do not necessarily reflect intra‐individual dynamics. Thus, in the present study, we analysed longitudinal data from three annual assessments of vocabulary and grammar in 217 children (M_age = 4 years and 3 months at first assessment) using a modelling strategy with some utility in distinguishing relations at the between‐ and within‐person levels. The results revealed strong correlations between grammar and vocabulary at the between‐person level, but the evidence of direct dependencies between the variables at the within‐person level was rather limited. Specifically, we found a small direct contribution from grammar to vocabulary for children between the ages of 4 and 5, but there was no evidence of any direct contributions from vocabulary to grammar. Further analyses suggested that the home literacy environment may represent a common source of individual differences in children's vocabulary and grammatical skills. In light of these results, we argue that the evidence of direct relations between vocabulary and grammatical development in preschool‐aged children may not be as strong as previously assumed.     

Extending the CLAST sequential rule to one-way ANOVA under group sampling

Several studies have demonstrated that the fixed-sample stopping rule (FSR), in which the sample size is determined in advance, is less practical and efficient than are sequential-stopping rules. The composite limited adaptive sequential test (CLAST) is one such sequential-stopping rule. Previous research has shown that CLAST is more efficient in terms of sample size and power than are the FSR and other sequential rules and that it reflects more realistically the practice of experimental psychology researchers. The CLAST rule has been applied only to thet test of mean differences with two matched samples and to the chi-square independence test for twofold contingency tables. The present work extends previous research on the efficiency of CLAST to multiple group statistical tests. Simulation studies were conducted to test the efficiency of the CLAST rule for the one-way ANOVA for fixed effects models. The ANOVA general test and two linear contrasts of multiple comparisons among treatment means are considered. The article also introduces four rules for allocatingN observations toJ groups under the general null hypothesis and three allocation rules for the linear contrasts. Results show that the CLAST rule is generally more efficient than the FSR in terms of sample size and power for one-way ANOVA tests. However, the allocation rules vary in their optimality and have a differential impact on sample size and power. Thus, selecting an allocation rule depends on the cost of sampling and the intended precision.