dpv {irtoys} | R Documentation |
Draws (by rejection sampling) plausible values from the posterior distribution of ability
dpv(resp, ip, mu=0, sigma=1, n=5)
resp |
A matrix of responses: persons as rows, items as columns, entries are either 0 or 1, no missing data |
ip |
Item parameters: a matrix with one row per item, and three columns: [,1] item discrimination a, [,2] item difficulty b, and [,3] asymptote c. |
mu |
Mean of the apriori distribution. Ignored when method="ML" . Default is 0. |
sigma |
Standard deviation of the apriori distribution. Ignored when method="ML" . Default is 1. |
n |
The number of plausible values to draw for each person (default is 5). |
A matrix with n
columns
Ivailo Partchev
data(Scored) p.2pl <- est(Scored, model="2PL", engine="ltm") plval <- dpv(resp=Scored, ip=p.2pl)