Description of Test
This was a modified version of the Ravens Matrices test that was previously used in the 10 Year study. The difficulty level at the top of the range of the test was extended by adding a new sub-test (F). At the lower end, sub-tests A and B were dropped. The test was further shortened by removing even-numbered items, so the remaining sub-tests (C, D, E, F) contained just 6 odd-numbered items each. A further change was the removal of the branching rule, although the discontinue rule was retained.
This test consisted of a series of incomplete patterns ("matrices"); in each case, the twin was asked to identify the missing part of the pattern. The twin did this by clicking on one of 8 possible missing parts. The patterns and missing parts are shown in full in a table below.
The test was divided into 4 sub-tests or sections, labelled C, D, E and F. Each sub-test consisted of 6 items, numbered 1, 3, 5, 7, 9 and 11 (even-numbered items from the original version of the test were dropped). Hence there were 24 items in total. Any given twin may have been presented with fewer than 24 items, because of the discontinue rule (described below). The sub-tests were presented in sequence (C then D then E then F). The discontinue rule applied independently within each sub-test, as described below.
This test was unaffected by item timeouts.
Test Rules
- Scoring
For each question, the correct response is given a score of 1, and any of the 7 incorrect responses is given a score of 0. The maximum total score for the test is 24. - Ordering of items
The 4 sub-tests are presented in sequence: C then D then E then F. Within each sub-test, items are presented in increasing numerical order of item number, subject to the discontinue rule below. - Discontinue rule
- Start with items 1, 3 and 5 in the sub-test.
- If items 1, 3 and 5 are all incorrect, discontinue the sub-test (skip items 7, 9 and 11). Move on to the next sub-test (or if in sub-test F, end the test).
- If at least one item is correct from items 1, 3 and 5, proceed with the rest of the sub-test (items 7, 9 and 11). Then move on to the next sub-test (or if in sub-test F, end the test).
Item Variables
The item variables relating to the Raven's 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 that the variable holding the total test score was also generated automatically on the web server. It is therefore treated as an item variable (it did not have to be derived as at age 10).
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 items skipped due to the discontinue rule, the item response variable is recoded from missing to -2, and the item score is recoded from missing to 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.
| Variables | Explanation | Values |
|---|---|---|
| lrvstat1/2 | Test status: outcome of test | 0=not started, 1=started but not finished, 2=successfully completed, 3=test crashed or otherwise compromised, 4=random responses |
| lrvdata1/2 | Data flag: is test data present in the dataset? | 0=no, 1=yes |
| lrvtot1/2 | Total score for this test, out of 24. | 0 to 24 (integer values) |
| lrvstdt1/2 | Start date of the test [not in dataset] | Date values |
| lrvsttm1/2 | Start time of the test [not in dataset] | Time values |
| lrvendt1/2 | End date of the test [not in dataset] | Date values |
| lrventm1/2 | End time of the test [not in dataset] | Time values |
| lrvsess1/2 | Number of sessions (at the computer) used by the twin to complete the test. | Integer values of 1 or above |
| lrvtime1/2 | Time taken to complete the test, in seconds | Integer values (number of seconds) |
| lrXYYan1/2 * | Item response (picture number selected, as tabulated below) | 1 to 8 (response picture selected). Also -2=discontinued, -4=item crashed. |
| lrXYYsc1/2 * | Item score (see table of items below for details) | 0=incorrect, 1=correct |
| lrXYYat1/2 * | Item answer time: length of time (in seconds) taken by the twin to respond to this item [not in dataset] | Integer values (number of seconds) |
| lrXYYdt1/2 * | Item download time: length of time (in seconds) between the end of the previous item and the start of this item; time needed to download files for this item [not in dataset] | Integer values (number of seconds) |
* XYY represents the item sub-test and number, where X is the sub-test (c/d/e/f) and YY is the item number within the sub-test (01, 03, 05, 07, 09 or 11).
Test Items
The numbering of the items, shown in the table below, equates to the numbering used in the item variables. The order in which items are presented in this table is the same as the order in which items are presented to the twins in the test, subject to the discontinue rule (see test rules above).
| item | correct response | picture |
|---|---|---|
| C1 | 8 |  |
| C3 | 3 |  |
| C5 | 7 |  |
| C7 | 5 |  |
| C9 | 7 |  |
| C11 | 1 |  |
| D1 | 3 |  |
| D3 | 3 |  |
| D5 | 8 |  |
| D7 | 5 |  |
| D9 | 1 |  |
| D11 | 5 |  |
| E1 | 7 |  |
| E3 | 8 |  |
| E5 | 1 |  |
| E7 | 1 |  |
| E9 | 3 |  |
| E11 | 4 |  |
| F1 | 7 |  |
| F3 | 7 |  |
| F5 | 6 |  |
| F7 | 4 |  |
| F9 | 5 |  |
| F11 | 3 |  |