# Item Response Theory and Computerized Adaptive Testing Functions

## Documentation for package ‘irt’ version 0.1.3

- DESCRIPTION file.

## Help Pages

$-method | Get slots from an 'Item-class' object.
$-method | Get slots of the an 'Item-class' object.
$-method | Access slots of a 'Testlet-class' object
$<--method | Set values to parameters or components of 'Item-class' object
$<--method | Set values to parameters or components of 'Item' class.
$<--method | Set values to parameters or components of 'Item' class.
add_misc | Add or change a named value to 'misc' slot of an 'Item-class', 'Itempool-class' or 'Testlet-class' object.
add_misc-method | Add or change a named value to 'misc' slot of an 'Item-class', 'Itempool-class' or 'Testlet-class' object.
as.data.frame.Item | Convert an 'Itempool-class' object into a 'data.frame'.
as.data.frame.Itempool | Convert an 'Itempool-class' object into a 'data.frame'.
as.data.frame.Testlet | Convert an 'Itempool-class' object into a 'data.frame'.
as.Itempool | Coerce a given object to 'Itempool-class' object
as.list.Itempool | This function converts Itempool objects to a list object
biserial | Calculate biserial correlation
c-method | Concatenate 'Item', 'Itempool' or 'Testlet' objects and return an Itempool object.
calculate_exposure_rates | Calculate exposure rate of items for CAT
calculate_overlap_rates | Calculate overlap rate of items for CAT
cat_sim | Computerized Adaptive Test (CAT) Simulation
cat_sim_fast | Computerized Adaptive Test (CAT) Simulation (Parallel Computing)
create_cat_design | Computerized Adaptive Test (CAT) Simulation Design
dif | Evaluate Differential Item Functioning (DIF) of a test
distractor_analysis | Distractor Analysis Function
est_ability | Ability Estimation of an examinee
est_bilog | Run BILOG-MG in batch mode
generate_ip | Generate a random 'Itempool' object
generate_item | Generate a random Item object
generate_testlet | Generate a random Testlet object
get_cat_administered_items | Get administered items from a CAT output
get_cat_response_data | Extracts the response data of CAT output.
get_max_possible_total_score | Calculate the maximum score of a set of items
info | Calculates the information of an "Item" object
info-method | Calculates the information of an "Item" object
ipd | Item Parameter Drift
irt | A Collection of Item Response Theory (IRT) and Computerized Adaptive Testing (CAT) Functions
is.Item | Check whether an object is an 'Item-class'
is.Itempool | Check whether an object is an 'Item-class'
is.Testlet | Check whether an object is an 'Item-class'
item | Create an 'Item' object
Item-class | An S4 class to represent an Item
itempool | Create an 'Itempool' object
Itempool-class | An S4 class to represent an Itempool
item_analysis | Item Analysis Function
item_fit | Calculate item-fit indices
length-method | Find the length of an 'Itempool-class' object
person_fit | Calculate person-fit indices
person_fit-method | Calculate person-fit indices
plot.Item | Plot Item Characteristic Curve of an 'Item' object
plot.Itempool | Plot Item Characteristic Curves or Test Characteristic Curve of an 'Itempool' object
plot_distractor_icc | Plot Empirical Item or Test characteristic curve
plot_empirical_icc | Plot Empirical Item or Test characteristic curve
plot_info | Plot Item Information Function
plot_resp_loglik | Plot the Log-Likelihood of a response string
prob | Calculate the probability of a correct response
prob-method | Calculate the probability of a correct response
resp_lik | Likelihood of a response string
resp_lik-method | Likelihood of a response string
resp_loglik | Log-likelihood of a Response String
resp_loglik-method | Log-likelihood of a Response String
rsss | Convert raw score to scale score and vice versa
sim_resp | Generate responses for a given model
sim_resp-method | Generate responses for a given model
summary.cat_output | Summarizes the raw output of cat_sim
testlet | Creates a 'Testlet-class' object
Testlet-class | An S4 class to represent a Testlet