TEDS Data Dictionary

Description of Test

In this test of language ability, twins were asked to match expressions (or figures of speech) having similar meanings. There were 11 items in the test. The items, together with the responses and correct answers, are shown in detail in the table of test items at the bottom of this page. Each item was presented in the following way:

1. The situation (context in which the expression is said) is played from an audio recording.
2. The expression (a figure of speech) is played from an audio recording.
3. The situation and expression are presented in text on the screen.
4. An audio recording now says "now listen to four expressions"; the four new expressions (A,B,C,D), which are the response options, immediately appear as text on the screen. (The situation and the original expression remain on screen as well.)
5. Each of the four new expressions in turn is played from an audio recording; while it is being played, the letter next to it (A/B/C/D) is highlighted on the screen.
6. An audio recording now says "now click on the choice which could be used instead of ...", and the original expression is repeated.
7. The twin selects a response by clicking on it.

As usual, a tutorial (including a practice item) was played before the test starts. The tutorial was used to establish whether the computer's sound is turned on, in order to discourage twins from attempting the test without sound.

Each item had a time limit of 60 seconds in which a twin had to answer. There were no branching or discontinue rules: each twin was presented with all 11 items, in numerical order.

Test Rules

• Scoring
  For each question, the correct response is given a score of 1, and any of the three incorrect responses is given a score of 0.
  The maximum total score for the test is 11.
• Ordering of items
  Items are presented in ascending order of item number. There are no branching or discontinue rules.
• Timeout rule
  Each item has a time limit of 1 minute within which a response must be given; timing starts after the four response expressions have all been played (in audio). If 1 minute passes without the twin giving a response, the item is forfeited (with score zero) and removed from the screen, to be replaced with a "next item" link to allow the twin to continue the test.

Item Variables

The item variables relating to the Expressions test, as listed in the table below, were generated automatically by programs on the web server during the course of the test. Note that the dataset only includes data for completed tests. If a twin started the test but left it unfinished, then the data for the test were not used. Note also that the variable holding the total test score was also generated automatically on the web server, so this is treated as an item variable, not a derived variable.

In most cases the values of these variables have been left unaltered, although some have been recoded during data cleaning as follows. See the web data cleaning page for further details.

• For timed out items, the item response variable is recoded from missing to -1, and the item answer time is recoded to missing (item scores are 0)
• For items that crashed or malfunctioned in any way, the item response variable is recoded from missing to -4, and the item score is recoded from missing to 0.
• For instances of crashed or otherwise compromised tests, the status flag is recoded from 2 to 3, the data flag is recoded from 1 to 0, and all item variables are recoded to missing (test data deleted)
• For twins identified as random responders in this test, the status flag is recoded from 2 to 4, the data flag is recoded from 1 to 0, and all item variables are recoded to missing (test data deleted)

The test start and end dates and times, and item answer and download times, have not been retained in the dataset.

Test Items

The numbering of the items, shown in the table below, equates to the numbering used in the item variables. This is the same as the order in which items were presented to twins in the test.