Publications
Peer-reviewed Journals:
2024:
Bratzke, D. (2024). Ebbinghaus, Müller-Lyer, and Ponzo: Three examples of bidirectional space-time interference. Psychonomic Bulletin & Review. https://doi.org/10.3758/s13423-024-02491-7
Hosch, A.-K., Hoffmann, J. A., & von Helversen, B. (2024). Category Learning in Context: Modelling an Assimilation Process in Self-regulated Category Learning. In Proceedings of the Annual Meeting of the Cognitive Science Society. (Vol. 46)
Danwitz, L., Hosch, A.-K. & von Helversen, B. (2024). Framing the Exploration-Exploitation Trade-Off: Distinguishing Between Minimizing Losses and Maximizing Gains. In Proceedings of the Annual Meeting of the Cognitive Science Society. (Vol. 46)
- Rosner, A., Brändli, F., & von Helversen, B. (2024). Eye movements as a tool to investigate exemplar retrieval in judgments. Judgment and Decision Making. 19, e8. https://doi.org/10.1017/jdm.2024.3
2023
- Oberauer, K., & Lin, H.-Y. (2023). An interference model for visual and verbal working memory. Journal of Experimental Psychology: Learning, Memory, and Cognition. Advance online publication. https://doi.org/10.1037/xlm0001303
- Hosch, A.-K., Wirtz, P., & von Helversen, B. (2023). Prior Experience of Variability Influences Generalization of Unspecified Categories. Quarterly Journal of Experimental Psychology. https://doi.org/10.1177/17470218231210491
- Hoffmann, J. A., & Hosch, A. K. (2023). Predicting serial position effects and judgment errors in retrospective evaluations from memory recall. Journal of Economic Psychology. https://doi.org/10.1016/j.joep.2023.102622
- Seitz, F., I., von Helversen, B., Albrecht, R., Rieskamp, J., & Jarecki, J. (2023). Testing three coping strategies for time pressure in categorizations and similarity judgments. Cognition, 233, 105358. https://doi.org/10.1016/j.cognition.2022.105358
2022
- Bratzke, D., Bryce, D. (2022). Subjective estimates of total processing time in dual-tasking: (some) good news for bad introspection. Psychological Research. https://doi.org/10.1007/s00426-022-01762-z
- Baumann, C., Schlegelmilch, R., & von Helversen, B. (2022). Adaptive behaviour in optimal sequential search. Journal of Experimental Psychology: General. Advance online publication. https://doi.org/10.1037/xge0001287
- Aubert, A., Lienert, J., & von Helversen, B. (2022). Gamified environmental multi-criteria decision analysis: Information on objectives and range insensitivity bias. International Transactions in Operational Research.https://doi.org/10.1111/itor.13206
- Inkster, A., Mitchell, C., Schlegelmilch, R., & Wills, A. (2022). Effect of a context shift on the inverse base rate effect. Open Journal of Experimental Psychology and Neuroscience, 1, 22–29. https://doi.org/10.46221/ojepn.2022.0404
- Bratzke, D., & Bryce, D. (2022). Timing of internal processes: Investigating introspection about the costs of task switching and memory search. Attention, Perception & Psychophysics, 84,1501–150. https://doi.org/10.3758/s13414-022-02510-6
- Danwitz, L., Mathar, D., Smith, E. et al. Parameter and Model Recovery of Reinforcement Learning Models for Restless Bandit Problems. Comput Brain Behav (2022). https://doi.org/10.1007/s42113-022-00139-0
- De Clercq, E., Grotzer, M., Landolt, M. A., von Helversen, B., Flury, M., Rössler, J., ... & Streuli, J. (2022). No wrong decisions in an all‐wrong situation. A qualitative study on the lived experiences of families of children with diffuse intrinsic pontine glioma. Pediatric Blood & Cancer, e29792. https://doi.org/10.1002/pbc.29792
- Rosner, A., Basieva, I., Barque-Duran, A., Gloeckner, A., von Helversen, B., Khrennikov, A., & Pothos E. (2022). Ambivalence in Decision Making: An Eye Tracking Study. Cognitive Psychology,134, 101464. https://doi.org/10.1016/j.cogpsych.2022.101464
- Lin, H.-Y., & Oberauer, K. (2022). An interference model for visual working memory: Applications to the change detection task. Cognitive Psychology, 133, 101463. https://doi.org/10.1016/j.cogpsych.2022.101463
- Rosner, A., Schaffner, M., & von Helversen, B. (2022). When the eyes have it and when not: How multiple sources of activation combine to guide eye movements during multiattribute decision making. Journal of Experimental Psychology: General, 151(6), 1394–1418. https://doi.org/10.1037/xge0000833
2021
- Schlegelmilch, R., Wills, A. J., & von Helversen, B. (2021). A cognitive category-learning model of rule abstraction, attention learning, and contextual modulation. Psychological Review. Advance online publication. https://doi.org/10.1037/rev0000321
- Bryce, D. & Bratzke, D. (2021). The surprising role of stimulus modality in the dual-task introspective blind spot: a memory account. Psychological Research. https://doi.org/10.1007/s00426-021-01545-y
- Bratzke, D. & Ulrich, R. (2021). Mental imagery of free fall: Does a falling apple accelerate in our minds? Timing & Time Perception. doi: 10.1163/22134468-bja10022
- Bernard, L. C., Lac, A., Richter, M., Cieciuch, J., Zuro, B., Silvestrini, N., ... & von Helversen, B. (2021). A cross-cultural study of purposive “traits of action”: measurement invariance of scales based on the action–trait theory of human motivation using exploratory structural equation modeling. Studia Psychologica: Theoria et Praxis, 21(1), 5-29. https://doi.org/10.21697/sp.2021.21.1.01
2020
- Koob, V., Durst, M., Bratzke, D., Ulrich, R., & Janczyk, M. (2020). S1-R2 and R1-R2 Backward Crosstalk both affect the central processing stage. Journal of Cognition, 3(1), 1-12.
- Baumann, C., Singmann, H., Gershman, S., & von Helversen, B. (2020). A Linear threshold model for optimal stopping behavior. Proceedings of the National Academy of Sciences. 117 (23), 12750-12755; https://doi.org/10.1073/pnas.2002312117
- Bratzke, D. & Ulrich, R. (2020). Short-term memory of temporal information revisited. Psychological Research. Advance online publication. doi:10.1007/s00426-020-01343-y
- Bratzke, D. & Janczyk, M. (2020). Introspection about backward crosstalk in dual-task performance. Psychological Research. Advance online publication. doi: 10.1007/s00426-019-01282-3.
- von Helversen, B., Coppin, G., & Scheibehenne, B. (2020). Money does not stink: Using unpleasant odors as stimulus material changes risky decision making. Journal of Behavioral Decision Making, 33(5), 593-605. https://doi.org/10.1002/bdm.2178
- Schlegelmilch, R., & von Helversen, B. (2020). The influence of reward magnitude on stimulus memory and stimulus generalization in categorization decisions. Journal of Experimental Psychology: General, 149(10), 1823–1854. https://doi.org/10.1037/xge0000747
- von Helversen, B., & Rieskamp, J. (2020). Stress‐related changes in financial risk taking: Considering joint effects of cortisol and affect. Psychophysiology, e13560. https://doi.org/10.1111/psyp.13560
- Albrecht, R., Hoffmann, J. A., Pleskac, T. J., Rieskamp, J., & von Helversen, B. (2020). Competitive retrieval strategy causes multimodal response distributions in multiple-cue judgments.Journal of Experimental Psychology: Learning, Memory, and Cognition, 46(6), 1064–1090. https://doi.org/10.1037/xlm0000772
2019
- Bratzke, D. & Ulrich, R. (2019). Temporal sequence discrimination within and across senses: Do we really hear what we see? Experimantal Brain Research, 237, 3089-3098. doi: 10.1007/s00221-019-05654-4.
- Bratzke, D. & Ulrich, R. (2019). Temporal reproduction within and across senses: Testing the supramodal property of the Pacemaker-Counter model. Journal of Experimental Psychology: Human Perception and Performance, 45, 1218-1235. doi: 10.1037/xhp0000667.
- Bratzke, D. & Bryce, D. (2019). Introspection is not always blind to the costs of multitasking: The case of task switching. Journal of Experimental Psychology: Learning, Memory,& Cognition, 45, 890-992. doi: 10.1037/xlm0000635.
- Hoffmann, J. A., von Helversen, B., & Rieskamp, J. (2019). Testing learning mechanisms of rule-based judgment. Decision, 6(4), 305–334.https://doi.org/10.1037/dec0000109
- Lin H.-Y & Oberauer K. (2019). How to Say No in Recognition Tests of Visual Working Memory: Testing Unidimensional and Two-Dimensional Models with Continuous or Discrete Memory States. Journal of Experimental Psychology: Learning, Memory, and Cognition.
- Rosner, A., & von Helversen, B. (2019). Memory shapes judgments: Tracing how memory biases judgments by inducing the retrieval of exemplars. Cognition, 190, 165-169. Doi:10.1016/j.cognition.2019.05.004
2018
- Hoffmann, J.A., von Helversen, B., Weilbächer, R., & Rieskamp, J. (2018). Tracing the path of forgetting in rule abstraction and exemplar retrieval. Quarterly Journal of Experimental Psychology.71, 2261-2281. doi: 10.1177/1747021817739861
- Oberauer K. & Lin H.-Y. (2018). An Interference Model of Visual Working Memory. Psychological Review, 124, 21-59
- Puskaric, M., von Helversen, B. & Rieskamp, J. (2018). Framing information as social influences information search and choice in probabilistic inference tasks. Acta Psychologica, 182, 166-176. Doi: 10.1016/j.actpsy.2017.08.004
- Rydzewska, K., von Helversen, B., Kossowska, M., Magnuski, M., Sedek, G. (2018). Age-Related Within-Task Adaptations in Sequential Decision Making: Considering Cognitive and Motivational Factors. Psychology and Aging,33(2), 297-314. doi:10.1037/pag0000239.
- von Helversen, B., Abramczuk, K., Kopéc. W., & Nielek, R. (2018). Influence of consumer reviews on online purchase decisions in older and younger adults. Decision Support Systems,113, 1-10. doi.:10.1016/j.dss.2018.05.006
- von Helversen, B., Mata. R., Samanez-Larkin, G.R., Wilke, A. (2018). Foraging, Exploration, or Search? On the (lack of) Convergent Validity Between Three Behavioral Paradigms. Evolutionary Behavioral Sciences.12(3), 152-162. https://doi.org/10.1037/ebs0000121
2017
- Bryce, D. & Bratzke, D. (2017). Are participants’ reports of their own reaction times reliable? Re-examining introspective limitations in active and passive dual-task paradigms. Acta Psychologica, 172, 1-9.
- Bratzke, D. , Birngruber, T., Durst, M., & Schröter, H. (2017). Filled and empty motor reproduction of filled and empty intervals: Is there also a filled-reproduction illusion? Attention, Perception, & Psychophysics, 79, 2143-2152.
- Hoffmann, J. A., Gaissmaier, W., & von Helversen. (2017). Justifying the judgment process neither affects judgment accuracy, nor strategy use. Judgment and Decision Making. 12(6), 627-641. https://doi.org/10.1017/S1930297500006744
- Oberauer K., Stoneking C., Wabersich D., & Lin H. (2017). Hierarchical Bayesian measurement models for continuous reproduction of visual features from working memory. Journal of Vision, 17, 1-27
- Puskaric, M., von Helversen, B., & Rieskamp, J. (2017). How social and non-social information influence classification decisions: A computational modeling approach. Quartely Journal of Experimental Psychology. 70, 1516-1534. doi: 10.1080/17470218.2016.1192209
2016
- Bausenhart, K. M., Bratzke, D. , & Ulrich, R. (2016). Formation and representation of temporal reference information. Current Opinion in Behavioral Sciences, 8, 46-52.
- Bratzke, D. & Bryce, D. (2016). Temporal discrimination of one’s own reaction times in dual-task performance: Context effects and methodological constraints. Attention, Perception, & Psychophysics, 78, 1806-1816.
- Bratzke, D. ,Quinn, K. R., Ulrich, R., & Bausenhart, K. (2016). Representations of temporal information in short-term memory: Are they modality-specific? Acta Psychologica, 170, 163-167.
- Bryce, D. & Bratzke, D. (2016). Multiple timing of nested intervals: Further evidence for a weighted sum of segments account. Psychonomic Bulletin & Review, 23, 317-323.
- Herzog, S. M., & von Helversen, B. (2016). Strategy selection versus strategy blending: A predictive perspective on single- and multi-strategy accounts in multiple-cue estimation. Journal of Behavioral Decision Making. Online first. doi:10.1002/bdm.1958
- Hoffmann, J. A., von Helversen, B., & Rieskamp, J. (2016). Similar task features shape judgment and categorization processes. Journal of Experimental Psychology: Learning, Memory and Cognition. 42, 1193-1217. doi:10.1037/xlm0000241
2015
- Bryce, D. & Bratzke, D. (2015). Are introspective reaction times affected by the method of time estimation? A comparison of visual analogue scales and reproduction. Attention, Perception & Psychophysics, 77, 978-984.
- Bryce, D. & Bratzke, D. (2015). How are overlapping intervals perceived? Evidence for a weighted sum of segments model. Acta Psychologica, 156, 83-95.
- Schröter, H., Bratzke, D. , Fiedler, A., & Birngruber, T. (2015). Does semantic redundancy gain result from multiple semantic priming? Acta Psychologica, 161, 79-85.
- Mata, R. & von Helversen, B. (2015) Search and the aging mind: The promise and limits of the cognitive control hypothesis of age differences in search. Topics in Cognitive Science.7, 416-427. doi: 10.1111/tops.12139
- Scheibehenne, B., & von Helversen, B. (2015). Selecting decision strategies: The differential role of affect. Cognition & Emotion.29,158-167 doi:10.1080/02699931.2014.896318
- Scheibehenne, B., & von Helversen, B., & Rieskamp. J. (2015). Different strategies for evaluating consumer products: Attribute- and exemplar-based approaches compared. Journal of Economic Psychology.46, 39–50. doi:10.1016/j.joep.2014.11.006
- Scholz, A., von Helversen, B., & Rieskamp, J. (2015). Eye movements reveal memory-processes during similarity versus rule-based decision making. Cognition, 136, 228-246. doi:10.1016/j.cognition.2014.11.019
2014
- Bratzke, D. , Bryce, D., & Seifried-Dübon, T. (2014). Distorted subjective reports of stimulus onsets under dual-task conditions: Delayed conscious perception or estimation bias? Consciousness and Cognition, 30, 36-47.
- Bratzke, D. , Schröter, H., & Ulrich, R. (2014). The role of consolidation for perceptual learning in temporal discrimination within and across modalities. Acta Psychologica, 147, 75-79.
- Bryce, D. & Bratzke, D. (2014). Introspective reports of reaction times in dual-tasks reflect experienced difficulty rather than timing of cognitive processes. Consciousness and Cognition, 27, 254-267.
- Hoffmann, J. A., von Helversen, B., & Rieskamp, J. (2014). Pillars of judgment: How memory abilities affect performance in rule-based and exemplar-based judgments, Journal of Experimental Psychology: General, 143(6), 2242–2261. doi:10.1037/a0037989
- Rerko, L., Oberauer, K., & Lin, H.-Y. (2014). Spatial transposition gradients in visual working memory. Quarterly Journal of Experimental Psychology, 67(1), 3–15.
- Rummer, R., Schweppe, J., Schlegelmilch, R., & Grice, M. (2014). Mood is linked to vowel type: The role of articulatory movements. Emotion, 14(2), 246.
- Shevchenko, Y., von Helversen, B. & Scheibehenne, B. (2014). Change and status quo in decisions with defaults: The effect of incidental emotions depends on the type of default. Judgment and Decision making, 9, 287-296.
- Souza, A. S., Rerko, L., Lin, H.-Y., & Oberauer, K. (2014). Focused attention improves working memory: Implications for flexible-resource and discrete-capacity models. Attention, Perception & Psychophysics.
- von Helversen, B. Karlsson, L., Rasch, B. Rieskamp, J. (2014). The neural substrate of strategy variety in human judgment. Frontiers in Human Neuroscience.8:809. doi: 10.3389/fnhum.2014.00809
- von Helversen, B, Herzog, S., M., & Rieskamp, J. (2014). Haunted by a doppelgänger: Irrelevant facial similarity affects rule-based judgments. Experimental Psychology, 61, 12-22, doi: 10.1027/1618-3169/a000221
2013
- Hoffmann, J. A., von Helversen, B., & Rieskamp, J. (2013). Deliberation’s blind sight: How cognitive load improves judgment processes. Psychological Science, 24, 869-879. doi: 10.1177/0956797612463581
- von Helversen, B., Karlsson, L., Mata, R., & Wilke, A. (2013). Why does cue polarity information provide benefits in inference problems? The role of strategy selection and knowledge of cue importance. Acta Psychologica, 144, 73-82. Doi: 10.1016/j.actpsy.2013.05.007
- von Helversen, B., Schooler, L., & Czienkowski, U. (2013). Are stripes beneficial? Dazzle camouflage influences perceived speed and hitting probability. PloS ONE. 8, e61173. doi:10.1371/journal.pone.0061173
2012
- Bratzke, D. , Seifried, T., & Ulrich, R. (2012). Perceptual learning in temporal discrimination: Asymmetric cross-modal transfer from audition to vision. Experimental Brain Research, 221, 205-210.
- Bratzke, D. , Steinborn, M. B., Rolke, B., & Ulrich, R. (2012b). Reply to: Testing of ’Executive Function’. Chronobiology International, 29, 1285.
- Bratzke, D. , Steinborn, M. B., Rolke, B., & Ulrich, R. (2012a). Effects of sleep loss and circadian rhythm on executive inhibitory control in the Stroop and Simon tasks. Chronobiology International, 29, 55-61.
- Leonhard, T., Bratzke, D. , Schröter, H., & Ulrich, R. (2012). Time-course analysis of temporal preparation on central processes. Psychological Research, 76, 236-251.
- Steinborn, M. B., Flehmig, H. C., Bratzke, D. , & Schröter, H. (2012). Error reactivity in self-paced performance. Highly-accurate individuals exhibit largest post-error slowing. Quarterly Journal of Experimental Psychology, 65, 624-631.
- Mata, R., Pachur, T., von Helversen, B., Hertwig, R., Rieskamp, J., & Schooler, L. (2012). Ecological Rationality: A Framework for Understanding and Aiding the Aging Decision Maker. Frontiers in Neuroscience, 6: 19.
- Mata, R. von Helversen, B., Karlsson, L., & Cüpper, L. (2012). Adult age differences in categorization and multiple-cue judgment. Developmental Psychology, 48, 1188-1201. doi: 10.1037/a0026084
- von Helversen, B., & Mata, R. (2012). Loosing a dime with a satisfied mind: Aging in sequential choice. Psychology and Aging, 27,825-839. doi: 10.1037/a0027845
2011
- Mata, R., von Helversen, B., & Rieskamp, J. (2011). When easy comes hard: The development of adaptive strategy selection. Child Development, 82, 687-700. Doi:10.1111/j.1467-8624.2010.01535.x
- von Helversen, B., Wilke, A., Johnson, T., Schmid, G. & Klapp, B. (2011). Performance benefits of depression: Sequential decision making in a healthy sample and a clinically depressed sample. Journal of Abnormal Psychology, 120, 962-968. doi: 10.1037/a0023238
- Yen, N. S. *, Tsai, J. L., Chen, P. L., Lin, H. Y., & Chen , A. L. P. (2011). Effects of typographic variables on eye movement measures in reading Chinese from the screen. Behavior & Information Technology.
2010
- Claros-Salinas, D., Bratzke, D. , & Schröter, H. (2010). Subjective and objective assessment of fatigue. Journal of the Neurological Sciences, 298, 165-166.
- Claros-Salinas, D., Bratzke, D. , Greitemann, G., Nickisch, N., Ochs, L., & Schröter, H. (2010). Fatigue-related diurnal variations of cognitive performance in multiple sclerosis and stroke patients. Journal of the Neurological Sciences, 295, 75-81.
- Steinborn, M. B., Bratzke, D. , Rolke, B., Gordijn, M. C. M., Beersma, D. G. M., & Ulrich, R. (2010). The effect of 40 hours of constant wakefulness on number comparison performance. Chronobiology International, 27, 807-825
- Steinborn, M. B., Rolke, B., Bratzke, D. , & Ulrich, R. (2010). The effect of a cross-trial shift of auditory warning signals on the sequential foreperiod effect. Acta Psychologica, 134, 94-104.
- Mata, R., von Helversen, B., & Rieskamp, J. (2010). Cognitive aging and strategy selection learning in decision making. Psychology and Aging, 25, 299-309.
- von Helversen, B., Mata, R. & Olsson, H. (2010). Do children profit from looking beyond looks? From similarity-based to cue-abstraction processes in multiple-cue judgment. Developmental Psychology, 46, 220-229.
2009
- Bratzke, D. , Rolke, B., & Ulrich, R. (2009). The source of execution-related dual-task interference: Motor bottleneck or response monitoring? Journal of Experimental Psychology: Human Perception and Performance, 35, 1413-1426.
- Bratzke, D. , Rolke, B., Steinborn, M. B., & Ulrich, R. (2009). The effect of 40 hours constant wakefulness on task-switching efficiency. Journal of Sleep Research, 18, 167-172.
- Steinborn, M. B., Rolke, B., Bratzke, D. , & Ulrich, R. (2009). Dynamic adjustment of temporal preparation: Shifting warning signal modality attenuates the sequential foreperiod effect. Acta Psychologica, 132, 40-47.
- von Helversen, B., & Rieskamp, J. (2009). Predicting Sentencing for Low Level Crimes: Comparing Models of Human Judgment. Journal of Experimental Psychology: Applied,15, 375-395.
- von Helversen, B., & Rieskamp, J. (2009). Models of Quantitative Estimations: Rule-based and Exemplar-Based Processes Compared. Journal of Experimental Psychology: Learning, Memory and Cognition, 35, 867-889.
2008
- Bratzke, D. , Ulrich, R., Rolke, B., Schröter, H., Jentzsch, I., & Leuthold, H. (2008). Motor limitation in dual-task processing with different effectors. Quarterly Journal of Experimental Psychology, 61, 1385-1399.
- Steinborn, M. B., Rolke, B., Bratzke, D. , & Ulrich, R. (2008). Sequential effects within a short foreperiod context: Evidence for the conditioning account of temporal preparation. Acta Psychologica, 129, 297-307.
- von Helversen, B., & Rieskamp, J. (2008). The mapping model: A cognitive theory of quantitative estimation. Journal of Experimental Psychology: General, 137, 73-96.
- von Helversen, B., Gendolla, G.H.E., Winkielman, P., & Schmidt, R. E. (2008). Exploring the hardship of ease: subjective and objective effort in the ease-of-processing paradigm. Motivation and Emotion, 32, 1-10.
2007
- Bratzke, D. , Rolke, B., Ulrich, R., & Peters, M. (2007). Central slowing during the night. Psychological Science, 18, 456-461.
Book Chapter:
2022
- Rydzewska, K., Koscielniak, M., von Helversen, B., & Sedek, G. (2022). Age differences in complex decision making and judgment. In G. Sedek, T. Hess & D. Touron (Eds). Multiple Pathways of Cognitive Aging: Motivational and Contextual Influences (203-234). New York, NY: Oxford University Press
2016
- von Helversen, B. (2016). Heuristiken bei Entscheidungen im Legalen Kontext. In S. Kirste. Interdisziplinarität in den Rechtswissenschaften: Ein interdisziplinärer und internationaler Dialog (pp 205-215). Berlin: Duncker & Humblot.
2009
- Hupfeld-Heinemann, J. & von Helversen, B. (2009). Models of decision-making on guilt and sanctions. In M. Oswald, S. Bieneck, & J. Hupfeld-Heinemann (Hrsg.). Social Psychology of Punishment of Crime (pp. 275-293). Chichester, UK: Wiley-Blackwell.
- Scheibehenne, B., & von Helversen, B. (2009). Useful heuristics. In T. Williams, K. Samset & K. J. Sunnevåg (Eds.). Making essential choices with scant information - front-end decision-making in major projects (pp. 194-211). Basingstoke: Palgrave Macmillan.
2008
- von Helversen, B., & Johnson, T. P. (2008). Der Einfluss von "Satisficing" und "Maximizing" auf das Entscheidungsverhalten. In W. Sarges & D. Scheffer. Innovative Ansätze für die Eignungsdiagnostik. Reihe: Psychologie für das Personalmanagement (pp. 265-273). Göttingen: Hogrefe.
Skripts und Code:
2019:
- Wills, A. J., Dome, L., Edmunds, C. E. R., Honke, G., Inkster, A. B., Schlegelmilch, R., & Spicer, S. (2019). catlearn: Formal psychological models of categorization and learning. Computer software manual].https://cran.r-project.org/web/packages/catlearn/index.html (R package version 0.6. 2).