Skip to contents

Administers the MST under five policies to the same examinees:

cold

Full routing module, population prior for routing and scoring.

prior_route

Full routing module, student's interim prior for routing only; population prior for the reported score.

prior_both

Interim prior for routing and for the reported score.

prior_short

Interim prior for routing with a shortened routing module (`short_n` items); population prior for scoring.

prior_only

Route on the interim prior alone (no routing module); population prior for scoring.

Usage

ty_policies(mst, theta, prior, population = NULL, short_n = 6, seed = NULL)

Arguments

mst

A `ty_mst`.

theta

True summative abilities.

prior

Student priors (`mean`, `sd`) from `predict()` on a `ty_link`.

population

Population prior `c(mean, sd)`; default: moments of the student priors' implied marginal.

short_n

Routing items for `prior_short`.

seed

Optional seed (each policy gets its own stream).

Value

A `ty_policies` object: named list of [ty_administer()] results, plus `theta`.

Examples

sim <- ty_simulate(n_calibration = 300, n_operational = 300, seed = 1)
op <- sim[sim$cohort == "operational", ]
prior <- predict(ty_link(sim), op)
pol <- ty_policies(ty_mst_default(), op$theta_S, prior, seed = 1)
summary(pol)
#>        policy   n routing_accuracy routed_too_easy routed_too_hard mean_items
#> 1        cold 300             0.73      0.12000000      0.15000000         36
#> 2 prior_route 300             0.87      0.05000000      0.08000000         36
#> 3  prior_both 300             0.86      0.05666667      0.08333333         36
#> 4 prior_short 300             0.83      0.06666667      0.10333333         30
#> 5  prior_only 300             0.82      0.07000000      0.11000000         24
#>           bias      rmse   mean_se
#> 1 -0.010955884 0.3519350 0.3488391
#> 2 -0.006595008 0.3514604 0.3461850
#> 3  0.009668233 0.2565423 0.2559708
#> 4  0.012397010 0.3756825 0.3723276
#> 5 -0.021422683 0.4211025 0.4077246