design_info function

Information about the design

This function is useful to inspect incomplete designs

design_info(dataSrc, predicate = NULL)

Arguments

• dataSrc: a connection to a dexter database, a matrix, or a data.frame with columns: person_id, item_id, item_score
• predicate: An optional expression to subset data, if NULL all data is used

Returns

a list with the following components

• design: a data.frame with columns booklet_id, item_id, item_position, n_persons
• connected_booklets: a data.frame with columns booklet_id, group; booklets with the same group are connected to each other.
• connected: TRUE/FALSE indicating whether the design is connected or not
• testlets: a data.frame with columns item_id and testlet; items within the same testlet always occur together in a booklet
• adj_matrix: list of two adjacency matrices: weighted_by_items and weighted_by_persons; These matrices can be useful in visually inspecting the design using a package like igraph