TY - JOUR A1 - Shaki, Samuel A1 - Pinhas, Michal A1 - Fischer, Martin H. T1 - Heuristics and biases in mental arithmetic BT - revisiting and reversing operational momentum JF - Thinking & Reasoning N2 - Mental arithmetic is characterised by a tendency to overestimate addition and to underestimate subtraction results: the operational momentum (OM) effect. Here, motivated by contentious explanations of this effect, we developed and tested an arithmetic heuristics and biases model that predicts reverse OM due to cognitive anchoring effects. Participants produced bi-directional lines with lengths corresponding to the results of arithmetic problems. In two experiments, we found regular OM with zero problems (e.g., 3+0, 3-0) but reverse OM with non-zero problems (e.g., 2+1, 4-1). In a third experiment, we tested the prediction of our model. Our results suggest the presence of at least three competing biases in mental arithmetic: a more-or-less heuristic, a sign-space association and an anchoring bias. We conclude that mental arithmetic exhibits shortcuts for decision-making similar to traditional domains of reasoning and problem-solving. KW - Heuristics KW - mental arithmetic KW - mental number line KW - operational momentum KW - problem-solving Y1 - 2017 U6 - https://doi.org/10.1080/13546783.2017.1348987 SN - 1354-6783 SN - 1464-0708 VL - 24 IS - 2 SP - 138 EP - 156 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Shaki, Samuel A1 - Fischer, Martin H. T1 - Competing Biases in Mental Arithmetic BT - When Division Is More and Multiplication Is Less JF - Frontiers in human neuroscience N2 - Mental arithmetic exhibits various biases. Among those is a tendency to overestimate addition and to underestimate subtraction outcomes. Does such “operational momentum” (OM) also affect multiplication and division? Twenty-six adults produced lines whose lengths corresponded to the correct outcomes of multiplication and division problems shown in symbolic format. We found a reliable tendency to over-estimate division outcomes, i.e., reverse OM. We suggest that anchoring on the first operand (a tendency to use this number as a reference for further quantitative reasoning) contributes to cognitive biases in mental arithmetic. KW - heuristics and biases KW - numerical cognition KW - mental arithmetic KW - mental number line KW - operational momentum Y1 - 2017 U6 - https://doi.org/10.3389/fnhum.2017.00037 SN - 1662-5161 VL - 11 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Mioni, Giovanna A1 - Fischer, Martin H. A1 - Shaki, Samuel T1 - Heuristics and biases in the mental manipulation of magnitudes BT - Evidence from length and time production JF - Quarterly journal of experimental psychology / published in association with Experimental Psychology Society N2 - There is a debate about whether and why we overestimate addition and underestimate subtraction results (Operational Momentum or OM effect). Spatial-attentional accounts of OM compete with a model which postulates that OM reflects a weighted combination of multiple arithmetic heuristics and biases (AHAB). This study addressed this debate with the theoretically diagnostic distinction between zero problems (e.g., 3 + 0, 3 - 0) and non-zero problems (e.g., 2 + 1, 4 - 1) because AHAB, in contrast to all other accounts, uniquely predicts reverse OM for the latter problem type. In two tests (line-length production and time production), participants indeed produced shorter lines and under-estimated time intervals in non-zero additions compared with subtractions. This predicted interaction between operation and problem type extends OM to non-spatial magnitudes and highlights the strength of AHAB regarding different problem types and modalities during the mental manipulation of magnitudes. They also suggest that OM reflects methodological details, whereas reverse OM is the more representative behavioural signature of mental arithmetic. KW - Heuristics and biases KW - mental arithmetic KW - operational momentum KW - SNARC KW - effect Y1 - 2021 U6 - https://doi.org/10.1177/1747021820967663 SN - 1747-0218 SN - 1747-0226 VL - 74 IS - 3 SP - 536 EP - 547 PB - SAGE Publishing CY - Thousand Oaks, CA ER - TY - INPR A1 - Kucian, Karin A1 - Plangger, Fabienne A1 - O'Gorman, Ruth A1 - von Aster, Michael G. T1 - Operational momentum effect in children with and without developmental dyscalculia T2 - Frontiers in psychology KW - developmental dyscalculia KW - operational momentum KW - children KW - learning disability KW - numerical cognition KW - mental number line KW - symbolic calculation KW - attention Y1 - 2013 U6 - https://doi.org/10.3389/fpsyg.2013.00847 SN - 1664-1078 VL - 4 IS - 45 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Hartmann, Matthias A1 - Mast, Fred W. A1 - Fischer, Martin H. T1 - Spatial biases during mental arithmetic: evidence from eye movements on a blank screen JF - Frontiers in psychology N2 - While the influence of spatial-numerical associations in number categorization tasks has been well established, their role in mental arithmetic is less clear. It has been hypothesized that mental addition leads to rightward and upward shifts of spatial attention (along the "mental number line"), whereas subtraction leads to leftward and downward shifts. We addressed this hypothesis by analyzing spontaneous eye movements during mental arithmetic. Participants solved verbally presented arithmetic problems (e.g., 2 + 7, 8-3) aloud while looking at a blank screen. We found that eye movements reflected spatial biases in the ongoing mental operation: Gaze position shifted more upward when participants solved addition compared to subtraction problems, and the horizontal gaze position was partly determined by the magnitude of the operands. Interestingly, the difference between addition and subtraction trials was driven by the operator (plus vs. minus) but was not influenced by the computational process. Thus, our results do not support the idea of a mental movement toward the solution during arithmetic but indicate a semantic association between operation and space. KW - mental arithmetic KW - eye movements KW - mental number line KW - operational momentum KW - embodied cognition KW - grounded cognition Y1 - 2015 U6 - https://doi.org/10.3389/fpsyg.2015.00012 SN - 1664-1078 VL - 6 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Fischer, Martin H. A1 - Shaki, Samuel T1 - Repeating Numbers Reduces Results: Violations of the Identity Axiom in Mental Arithmetic JF - Frontiers in psychology N2 - Even simple mental arithmetic is fraught with cognitive biases. For example, adding repeated numbers (so-called tie problems, e.g., 2 + 2) not only has a speed and accuracy advantage over adding different numbers (e.g., 1 + 3) but may also lead to under-representation of the result relative to a standard value (Charras et al., 2012, 2014). Does the tie advantage merely reflect easier encoding or retrieval compared to non-ties, or also a distorted result representation? To answer this question, 47 healthy adults performed two tasks, both of which indicated under-representation of tie results: In a result-to-position pointing task (Experiment 1) we measured the spatial mapping of numbers and found a left-bias for tie compared to non-tie problems. In a result-to-line-length production task (Experiment 2) we measured the underlying magnitude representation directly and obtained shorter lines for tie-compared to non-tie problems. These observations suggest that the processing benefit of tie problems comes at the cost of representational reduction of result meaning. This conclusion is discussed in the context of a recent model of arithmetic heuristics and biases. KW - AHAB KW - cognitive bias KW - mental arithmetic KW - numerical cognition KW - operational momentum KW - SNARC KW - tie problems Y1 - 2018 U6 - https://doi.org/10.3389/fpsyg.2018.02453 SN - 1664-1078 VL - 9 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Fischer, Martin H. A1 - Miklashevsky, Alex A. A1 - Shaki, Samuel T1 - Commentary : The Developmental Trajectory of the Operational Momentum Effect JF - Frontiers in Psychology KW - embodied cognition KW - operational momentum KW - SNARC effect KW - mental arithmetic KW - numerical cognition Y1 - 2018 U6 - https://doi.org/10.3389/fpsyg.2018.02259 SN - 1664-1078 N1 - A Commentary on The Developmental Trajectory of the Operational Momentum Effect by Pinheiro-Chagas, P., Didino, D., Haase, V. G., Wood, G., and Knops, A. (2018). Front. Psychol. 9:1062 doi: 10.3389/fpsyg.2018.01062 VL - 9 PB - Frontiers Research Foundation CY - Lausanne ER -