@article{FischerMiklashevskyShaki2018, author = {Fischer, Martin H. and Miklashevsky, Alex A. and Shaki, Samuel}, title = {Commentary : The Developmental Trajectory of the Operational Momentum Effect}, series = {Frontiers in Psychology}, volume = {9}, journal = {Frontiers in Psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2018.02259}, pages = {3}, year = {2018}, language = {en} } @misc{FischerMiklashevskyShaki2019, author = {Fischer, Martin H. and Miklashevsky, Alex A. and Shaki, Samuel}, title = {Commentary : The Developmental Trajectory of the Operational Momentum Effect}, series = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe}, number = {502}, issn = {1866-8364}, doi = {10.25932/publishup-42316}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-423169}, pages = {3}, year = {2019}, language = {en} } @article{ShakiFischer2017, author = {Shaki, Samuel and Fischer, Martin H.}, title = {Competing Biases in Mental Arithmetic}, series = {Frontiers in human neuroscience}, volume = {11}, journal = {Frontiers in human neuroscience}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1662-5161}, doi = {10.3389/fnhum.2017.00037}, year = {2017}, abstract = {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.}, language = {en} } @misc{ShakiFischer2017, author = {Shaki, Samuel and Fischer, Martin H.}, title = {Competing Biases in Mental Arithmetic}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-103492}, pages = {5}, year = {2017}, abstract = {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.}, language = {en} } @article{ShakiPinhasFischer2017, author = {Shaki, Samuel and Pinhas, Michal and Fischer, Martin H.}, title = {Heuristics and biases in mental arithmetic}, series = {Thinking \& Reasoning}, volume = {24}, journal = {Thinking \& Reasoning}, number = {2}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {1354-6783}, doi = {10.1080/13546783.2017.1348987}, pages = {138 -- 156}, year = {2017}, abstract = {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.}, language = {en} } @article{MioniFischerShaki2021, author = {Mioni, Giovanna and Fischer, Martin H. and Shaki, Samuel}, title = {Heuristics and biases in the mental manipulation of magnitudes}, series = {Quarterly journal of experimental psychology / published in association with Experimental Psychology Society}, volume = {74}, journal = {Quarterly journal of experimental psychology / published in association with Experimental Psychology Society}, number = {3}, publisher = {SAGE Publishing}, address = {Thousand Oaks, CA}, issn = {1747-0218}, doi = {10.1177/1747021820967663}, pages = {536 -- 547}, year = {2021}, abstract = {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.}, language = {en} } @article{FischerShaki2018, author = {Fischer, Martin H. and Shaki, Samuel}, title = {Repeating Numbers Reduces Results: Violations of the Identity Axiom in Mental Arithmetic}, series = {Frontiers in psychology}, volume = {9}, journal = {Frontiers in psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2018.02453}, pages = {9}, year = {2018}, abstract = {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.}, language = {en} }