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predictWEV_Conf predicts the categorical response distribution of decision and confidence ratings, predictWEV_RT computes the predicted RT distribution (density) in the 2DSD Model (Pleskac & Busemeyer, 2010) and the dynWEV model (Hellmann et al., 2023), given specific parameter constellations. See dWEV and d2DSD for more information about parameters.

Usage

predictWEV_Conf(paramDf, model = "dynaViTE", maxrt = 15,
  subdivisions = 100L, simult_conf = FALSE, stop.on.error = FALSE,
  precision = 1e-05, .progress = TRUE)

predictWEV_RT(paramDf, model = NULL, maxrt = 9, subdivisions = 100L,
  minrt = NULL, simult_conf = FALSE, scaled = FALSE, DistConf = NULL,
  precision = 1e-05, .progress = TRUE)

Arguments

paramDf

a list or dataframe with one row. Column names should match the names of dynaViTE and 2DSD model specific parameter names. For different stimulus quality/mean drift rates, names should be v1, v2, v3,.... Different sv and/or s parameters are possible with sv1, sv2, sv3... (s1, s2, s3,... respectively) with equally many steps as for drift rates. Additionally, the confidence thresholds should be given by names with thetaUpper1, thetaUpper2,..., thetaLower1,... or, for symmetric thresholds only by theta1, theta2,....

model

character scalar. One of "dynaViTE", "dynWEV", or "2DSD".

maxrt

numeric. The maximum RT for the integration/density computation. Default: 15 (for predictWEV_Conf (integration)), 9 (for predictWEV_RT).

subdivisions

integer (default: 100). For predictWEV_Conf it is used as argument for the inner integral routine. For predictWEV_RT it is the number of points for which the density is computed.

simult_conf

logical. Whether in the experiment confidence was reported simultaneously with the decision, as then decision and confidence judgment are assumed to have happened subsequent before response and computations are different, when there is an observable interjudgment time (then simult_conf should be FALSE).

stop.on.error

logical. Argument directly passed on to integrate. Default is FALSE, since the densities invoked may lead to slow convergence of the integrals (which are still quite accurate) which causes R to throw an error.

precision

numerical scalar value. Precision of calculation. Corresponds to the step size of integration w.r.t. z and t0. Default is 1e-5.

.progress

logical. if TRUE (default) a progress bar is drawn to the console.

minrt

numeric or NULL(default). The minimum rt for the density computation.

scaled

logical. For predictWEV_RT. Whether the computed density should be scaled to integrate to one (additional column densscaled). Otherwise the output contains only the defective density (i.e. its integral is equal to the probability of a response and not 1). If TRUE, the argument DistConf should be given, if available. Default: FALSE.

DistConf

NULL or data.frame. A data.frame or matrix with column names, giving the distribution of response and rating choices for different conditions and stimulus categories in the form of the output of predictWEV_Conf. It is only necessary, if scaled=TRUE, because these probabilities are used for scaling. If scaled=TRUE and DistConf=NULL, it will be computed with the function predictWEV_Conf, which takes some time and the function will throw a message. Default: NULL

Value

predictWEV_Conf returns a data.frame/tibble with columns: condition, stimulus, response, rating, correct, p, info, err. p is the predicted probability of a response and rating, given the stimulus category and condition. info and err refer to the respective outputs of the integration routine used for the computation. predictWEV_RT returns a data.frame/tibble with columns: condition, stimulus, response, rating, correct, rt and dens (and densscaled, if scaled=TRUE).

Details

The function predictWEV_Conf consists merely of an integration of the response time density, dWEV and d2DSD, over the response time in a reasonable interval (t0 to maxrt). The function predictWEV_RT wraps these density functions to a parameter set input and a data.frame output. For the argument paramDf, the output of the fitting function fitRTConf with the respective model may be used.

Note

Different parameters for different conditions are only allowed for drift rate v, drift rate variability sv, and process variability s. Otherwise, s is not required in paramDf but set to 1 by default. All other parameters are used for all conditions.

References

Hellmann, S., Zehetleitner, M., & Rausch, M. (2023). Simultaneous modeling of choice, confidence and response time in visual perception. Psychological Review 2023 Mar 13. doi: 10.1037/rev0000411. Epub ahead of print. PMID: 36913292.

Pleskac, T. J., & Busemeyer, J. R. (2010). Two-Stage Dynamic Signal Detection: A Theory of Choice, Decision Time, and Confidence, Psychological Review, 117(3), 864-901. doi:10.1037/a0019737

Author

Sebastian Hellmann.

Examples

# Examples for "dynWEV" model (equivalent applicable for "2DSD" model (with less parameters))
# 1. Define some parameter set in a data.frame
paramDf <- data.frame(a=2.5,v1=0.5, v2=1, t0=0.1,z=0.55,
                      sz=0,sv=0.2, st0=0,  tau=3, w=0.3,
                      theta1=0.8, svis=0.5, sigvis=0.8)

# 2. Predict discrete Choice x Confidence distribution:
preds_Conf <- predictWEV_Conf(paramDf, "dynWEV", maxrt = 15)
head(preds_Conf)
#>   condition stimulus response correct rating          p info          err
#> 1         1        1        1       1      1 0.22413378   OK 3.643298e-06
#> 2         2        1        1       1      1 0.08306176   OK 2.343204e-06
#> 3         1       -1        1       0      1 0.11181226   OK 2.052870e-06
#> 4         2       -1        1       0      1 0.02919229   OK 1.178054e-06
#> 5         1        1       -1       0      1 0.07659838   OK 1.588271e-05
#> 6         2        1       -1       0      1 0.01620841   OK 5.775923e-05
# \donttest{
  # To set simult_conf=TRUE makes a minor difference in the discrete distribution,
  # because we integrate over response times (we just adapt maxrt for comparison)
  preds_Conf2 <- predictWEV_Conf(paramDf, "dynWEV", simult_conf = TRUE, maxrt = 15+paramDf$tau)
  summary(preds_Conf$p-preds_Conf2$p) # difference in predicted probabilities
#>       Min.    1st Qu.     Median       Mean    3rd Qu.       Max. 
#> -1.609e-06 -2.617e-07  2.548e-10 -2.090e-07  7.731e-10  8.196e-09 
# }

# 3. Compute RT density
preds_RT <- predictWEV_RT(paramDf, "dynWEV", maxrt=4, subdivisions=200) #(scaled=FALSE)
# same output with scaled density column:
preds_RT <- predictWEV_RT(paramDf, "dynWEV", maxrt=4, subdivisions=200,
                         scaled=TRUE, DistConf = preds_Conf)
head(preds_RT)
#>   condition stimulus response correct rating        rt         dens
#> 1         1        1        1       1      1 0.1000000 0.000000e+00
#> 2         1        1        1       1      1 0.1195980 7.844018e-13
#> 3         1        1        1       1      1 0.1391960 2.838316e-06
#> 4         1        1        1       1      1 0.1587940 3.346474e-04
#> 5         1        1        1       1      1 0.1783920 3.193339e-03
#> 6         1        1        1       1      1 0.1979899 1.144218e-02
#>     densscaled
#> 1 0.000000e+00
#> 2 3.499704e-12
#> 3 1.266349e-05
#> 4 1.493070e-03
#> 5 1.424747e-02
#> 6 5.105068e-02
# \donttest{
  # produces a warning, if scaled=TRUE and DistConf missing
  preds_RT <- predictWEV_RT(paramDf, "dynWEV", maxrt=4, subdivisions=200,
                           scaled=TRUE)
#> scaled is TRUE and DistConf is NULL. The rating distribution will be computed, which will take additional time.
# }

# \donttest{
  # Example of visualization
  library(ggplot2)
  preds_Conf$rating <- factor(preds_Conf$rating, labels=c("unsure", "sure"))
  preds_RT$rating <- factor(preds_RT$rating, labels=c("unsure", "sure"))
  ggplot(preds_Conf, aes(x=interaction(rating, response), y=p))+
    geom_bar(stat="identity")+
    facet_grid(cols=vars(stimulus), rows=vars(condition), labeller = "label_both")

  ggplot(preds_RT, aes(x=rt, color=interaction(rating, response), y=dens))+
    geom_line(stat="identity")+
    facet_grid(cols=vars(stimulus), rows=vars(condition), labeller = "label_both")+
    theme(legend.position = "bottom")

  ggplot(aggregate(densscaled~rt+correct+rating+condition, preds_RT, mean),
         aes(x=rt, color=rating, y=densscaled))+
    geom_line(stat="identity")+
    facet_grid(cols=vars(condition), rows=vars(correct), labeller = "label_both")+
    theme(legend.position = "bottom")

# }
# Use PDFtoQuantiles to get predicted RT quantiles
head(PDFtoQuantiles(preds_RT, scaled = FALSE))
#> # A tibble: 6 × 7
#>   condition stimulus response correct rating     p     q
#>       <int>    <dbl>    <dbl>   <dbl> <fct>  <dbl> <dbl>
#> 1         1       -1       -1       1 unsure   0.1 0.531
#> 2         1       -1       -1       1 unsure   0.3 0.845
#> 3         1       -1       -1       1 unsure   0.5 1.20 
#> 4         1       -1       -1       1 unsure   0.7 1.71 
#> 5         1       -1       -1       1 unsure   0.9 2.67 
#> 6         1       -1       -1       1 sure     0.1 0.531