DOI QR코드

DOI QR Code

Analysis tool for the diffusion model using GPU: SNUDM-G

GPU를 이용한 확산모형 분석 도구: SNUDM-G

  • Lee, Dajung (Department of Psychology, Seoul National University) ;
  • Lee, Hyosun (Cognitive Program, Seoul National University) ;
  • Koh, Sungryong (Department of Psychology, Seoul National University)
  • 이다정 (서울대학교 심리학과) ;
  • 이효선 (서울대학교 인지과학협동과정) ;
  • 고성룡 (서울대학교 심리학과)
  • Received : 2022.09.08
  • Accepted : 2022.09.16
  • Published : 2022.09.30

Abstract

In this paper, we introduce the SNUDM-G, a diffusion model analysis tool with improved computational speed. Although the diffusion model has been applied to explain various cognitive tasks, its use was limited due to computational difficulties. In particular, SNUDM(Koh et al., 2020), one of the diffusion model analysis tools, has a disadvantage in terms of processing speed because it sequentially generates 20,000 data when approximating the diffusion process. To overcome this limitation, we propose to use graphic processing units(GPU) in the process of approximating the diffusion process with a random walk process. Since 20,000 data can be generated in parallel using the graphic processing units, the estimation speed can be increased compared to generating data through sequential processing. As a result of analyzing the data of Experiment 1 by Ratcliff et al. (2004) and recovering the parameters with SNUDM-G using GPU and SNUDM using CPU, SNUDM-G estimated slightly higher values for certain parameters than SNUDM. However, in term of computational speed, SNUDM-G estimated the parameters much faster than SNUDM. This result shows that a more efficient diffusion model analysis for various cognitive tasks is possible using this tool and further suggests that the processing speed of various cognitive models can be improved by using graphic processing units in the future.

이 논문에서는 계산 속도를 개선한 확산모형 분석 도구 SNUDM-G를 소개한다. 확산모형은 다양한 인지과제를 설명하는 데에 적용되어 왔음에도 불구하고 계산적 어려움으로 인해 사용에 제한이 있었다. 특히 확산모형 분석 도구 중 하나인 SNUDM(고성룡 등, 2020)은 확산과정을 근사할 때 2만 개의 자료를 순차적으로 생성하기 때문에 처리 속도 면에서 단점이 있다. 이러한 한계를 극복하기 위해 확산과정을 무작위걷기 방법으로 근사하는 과정에서 그래픽처리장치(GPU)를 사용할 것을 제안한다. 그래픽처리장치를 사용하면 2만 개의 자료를 병렬로 생성할 수 있기 때문에 순차처리로 자료를 생성하는 것에 비해 분석의 속도를 높일 수 있다. GPU를 사용한 SNUDM-G와 CPU를 사용한 SNUDM으로 Ratcliff 등 (2004)의 실험 1 자료를 분석하고 매개변수 복구를 한 결과 SNUDM-G가 SNUDM보다 특정 매개변수에서 다소 높은 값을 추정하였으나, 계산 속도 면에서는 큰 차이로 SNUDM-G가 SNUDM보다 더 빠르게 매개변수를 추정하였다. 이 결과는 이 도구를 이용하여 다양한 인지 과제에 대해 보다 효율적인 확산모형 분석이 가능할 것임을 보여주며, 더 나아가 앞으로 그래픽처리장치를 이용하여 다양한 인지 모형의 처리 속도를 개선할 수 있음을 시사한다.

Keywords

References

  1. 고성룡, 주혜리, 이다정. (2020). 확산모형 분석도구: SNUDM. 인지과학, 31(1), 1-23. https://doi.org/10.19066/cogsci.2020.31.1.1
  2. Amold, N. R., Broder, A., & Bayen, U. J. (2015). Empirical validation of the diffusion model for recognition memory and a comparison of parameter-estimation methods. Psychological Research, 79(5), 882-898. https://doi.org/10.1007/s00426-014-0608-y
  3. Brown, S., Ratcliff, R., & Smith, P. L. (2006). Evaluating methods for approximating stochastic differential equations. Journal of Mathematical Psychology, 50, 401-410.
  4. Feller, W. (1968). An introduction to probability theory and its applications. New York: Wiley.
  5. Kuroiwa, R., & Fukunaga, A. (2018). Batch random walk for GPU-based classical planning. In Twenty-Eighth International Conference on Automated Planning and Scheduling.
  6. Lerche, V., & Voss, A. (2017). Experimental validation of the diffusion model based on a slow response time paradigm. Psychological Research, 83(6), 1194-1209. https://doi.org/10.1007/s00426-017-0945-8
  7. Luersen, M. A., Le Riche, R., & Guyon, F. (2004). A constrained, globalized, and bounded NelderMead method for engineering optimization. Structural and Multidisciplinary Optimization 27(1), 43-54. https://doi.org/10.1007/s00158-003-0320-9
  8. Nelder, J. A., & Mead, R. (1965). A simplex method for function minimization. Computer Journal, 7, 308-313. https://doi.org/10.1093/comjnl/7.4.308
  9. Ratcliff, R. (1978). A theory of memory retrieval. Psychological Review, 85, 59-108. https://doi.org/10.1037/0033-295X.85.2.59
  10. Ratcliff, R. (1981). A theory of order relations in perceptual matching. Psychological Review, 88, 552-572. https://doi.org/10.1037/0033-295X.88.6.552
  11. Ratcliff, R. (2014). Measuring psychometric functions with the diffusion model. Journal of Experimental Psychology: Human Perception and Performance, 40, 870-888. https://doi.org/10.1037/a0034954
  12. Ratcliff, R., Gomez, P., & McKoon, G. (2004). A diffusion model account of the lexical decision task. Psychological Review, 111(1), 159-182. https://doi.org/10.1037/0033-295x.111.1.159
  13. Ratcliff, R., & McKoon, G. (2008). The diffusion decision model: Theory and data for two-choice decision tasks. Neural Computation, 20, 873-922. https://doi.org/10.1162/neco.2008.12-06-420
  14. Ratcliff, R., & Rounder, J. N. (1998). Modeling response times for two-choice decisions. Psychological Science, 9, 347-356. https://doi.org/10.1111/1467-9280.00067
  15. Ratcliff, R., Smith, P. L., Brown, S. D., & McKoon, G. (2016). Diffusion decision model: Current issues and history. Trends in Cognitive Sciences, 20, 260-281. https://doi.org/10.1016/j.tics.2016.01.007
  16. Ratcliff, R., Thapar, A., & McKoon, G. (2001). The effects of aging on reaction time in a signal detection task. Psychology and Aging, 16, 323-341. https://doi.org/10.1037/0882-7974.16.2.323
  17. Ratcliff, R., Thapar, A., & McKoon, G. (2010). Individual differences, aging, and IQ in two-choice tasks. Cognitive Psychology, 60, 127-157. https://doi.org/10.1016/j.cogpsych.2009.09.001
  18. Ratclliff, R., & Tuerlinckx, F. (2002). Estimating paramters of the diffusion model: Approaches to dealing with contaminant reaction times and parameter variability. Psychonomic Bulletin & Review, 9, 438-481. https://doi.org/10.3758/BF03196302
  19. Ratcliff, R., Vand Zandt, T., & McKoon, G. (1999). Connectionist and diffusion models of reaction time. Psychological Review, 106, 261-300. https://doi.org/10.1037/0033-295X.106.2.261
  20. Starns, J. J., & Ratcliff, R. (2010). The effects of aging on the speed-accuracy compromise: Boundary optimality in the diffusion model. Psychology and Aging, 25, 377-390. https://doi.org/10.1037/a0018022
  21. Starns, J. J., & Ratcliff, R. (2012). Age-related differences in diffusion model boundary optimality with both trial-limited and time-limited tasks. Psychonomic Bulletin & Review, 19, 139-145. https://doi.org/10.3758/s13423-011-0189-3
  22. Usher, M., & McClelland, J. L. (2001). The time course of perceptual choice: The leaky, competing accumulator model. Psychological Review, 108(3), 550. https://doi.org/10.1037/0033-295X.108.3.550
  23. Verdonck S., Meers, K., & Tuerlincks, F. (2016). Efficient simulation of diffusion-based choice RT models on CPU and GPU. Behavior Research Methods, 48(1), 13-27. https://doi.org/10.3758/s13428-015-0569-0
  24. Voss, A., Lerche, V., Mertens, U., & Voss, J. (2019). Sequential sampling models with variable boundaries and non-normal noise: A comparison of six models. Psychonomic Bulletin & Review, 26(3), 813-832. https://doi.org/10.3758/s13423-018-1560-4
  25. Voss, A., Rothermund, K., & Voss, J. (2004). Interpreting the parameters of the diffusion model: An empirical validation. Memory & Cognition, 32, 1206-1220. https://doi.org/10.3758/BF03196893
  26. Voss, A., & Voss, J. (2007). Fast-Dm: A free program for efficient diffusion model analysis. Behavior Research Methods, 39(4), 767-775. https://doi.org/10.3758/BF03192967
  27. Voss, A., & Voss, J. (2008). A fast numerical algorithm for the estimation of diffusion model parameters. Journal of Mathematical Psychology, 52(1), 1-9. https://doi.org/10.1016/j.jmp.2007.09.005
  28. Wagenmakers, E. J., Van Der Maas, H. L., & Grasman, R. P. (2007). An EZ-diffusion model for response time and accuracy. Psychonomic Bulletin & Review, 14(1), 3-22. https://doi.org/10.3758/BF03194023