TY  - JOUR
A1  - Miller, Jeff
A1  - Schwarz, Wolfgang
T1  - Delta plots for conflict tasks
BT  - an activation-suppression race model
JF  - Psychonomic bulletin & review : a journal of the Psychonomic Society
N2  - We describe a mathematically simple yet precise model of activation suppression that can explain the negative-going delta plots often observed in standard Simon tasks. The model postulates a race between the identification of the relevant stimulus attribute and the suppression of irrelevant location-based activation, with the irrelevant activation only having an effect if the irrelevant activation is still present at the moment when central processing of the relevant attribute starts. The model can be fitted by maximum likelihood to observed distributions of RTs in congruent and incongruent trials, and it provides good fits to two previously-reported data sets with plausible parameter values. R and MATLAB software for use with the model is provided.
KW  - Delta plots
KW  - RT models
KW  - Simon effect
KW  - Activation suppression model
Y1  - 2021
U6  - https://doi.org/10.3758/s13423-021-01900-5
SN  - 1069-9384
SN  - 1531-5320
VL  - 28
IS  - 6
SP  - 1776
EP  - 1795
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Schwarz, Wolfgang
A1  - Miller, Jeff
T1  - Response time models of delta plots with negative-going slopes
JF  - Psychonomic bulletin & review : a journal of the Psychonomic Society
N2  - Delta plots (DPs) graphically compare reaction time (RT) quantiles obtained under two experimental conditions. In some research areas (e.g., Simon effects), decreasing delta plots (nDPs) have consistently been found, indicating that the experimental effect is largest at low quantiles and decreases for higher quantiles. nDPs are unusual and intriguing: They imply that RT in the faster condition is more variable, a pattern predicted by few standard RT models. We describe and analyze five classes of well-established latency mechanisms that are consistent with nDPs-exhaustive processing models, correlated stage models, mixture models, cascade models, and parallel channels models-and discuss the implications of our analyses for the interpretation of DPs. DPs generally do not imply any specific processing model; therefore, it is more fruitful to start from a specific quantitative model and to compare the DP it predicts with empirical data.
KW  - Delta plot
KW  - RT models
KW  - Simon effect
KW  - Activation suppression model
Y1  - 2012
U6  - https://doi.org/10.3758/s13423-012-0254-6
SN  - 1069-9384
VL  - 19
IS  - 4
SP  - 555
EP  - 574
PB  - Springer
CY  - New York
ER  -