TEDS Data Dictionary

The 18 Year Kings Challenge Mazes Test

Contents of this page:

Introduction
Description
Web Test Rules
Dataset Item Variables
Table of Test Items

Introduction

This page describes the Mazes test, one of the web activities in the battery of the 18 Year Kings Challenge twin web study. The Mazes test was the tenth and final test in the battery.

Description

In the web presentation, the Mazes test was introduced to twins as an activity called "The Gem of Light", with the following text: "The final hour draws near. The enemy forces are surrounding us as we speak, and the Iron Cannon is ready to spit fire. Wait ... can it be true? The ancient scrolls have revealed maps showing the location of the Gem of Light - be quick and choose the right path!" This text was accompanied by the image below:

The test itself consisted of a practice item followed by 10 scored test items. Each item consisted of a stimulus image and between 4 and 12 response options labelled 1A, 1B, 2A, 2B and so on. The stimulus was an image of a maze labelled with two or three "entrances" (labelled 1, 2, 3) and with 2, 3 or 4 "exits" (labelled A, B, C, D). Twins were asked to select the response that represented the only valid route through the maze from an entrance to an exit, for example 1A from entrance 1 to exit A. Twins responded by clicking on one of the response options. On clicking, the response was immediately submitted to the web server, and the next item was presented. A full table of test items, including stimulus and response images, can be found below under the heading Table of Test Items.

The test was preceded by an instructions page, which is reproduced here, and which illustrates the nature of the test items:
Mazes test instructions

The instructions page was followed by a single practice item. The practice item was optional: a twin could skip the practice item, attempt it once, or attempt it many times if they wished. On each attempt of the practice item, the twin was presented with feedback to say whether they chose the correct response, and what the correct response should have been. No such feedback was given after the main test items. No data for the practice item is included in the dataset.

The 10 main test items (subject to a discontinue rule) followed immediately after the practice item. The items were presented in numerical item number order, without any branching. Each item had a 25 second time limit, and a count-down timer was shown at the top-left corner of the page for every item, as a reminder of this.

Twins were encouraged to complete the test in one session if possible. Hence, no "come back later" button was placed on screen at any stage. However, it was possible to halt a test, by closing the browser or turning off the computer. After halting the test, it was possible for a twin to resume at a later time or date by logging in again: they would be presented with the next item to be attempted.

An individual test item could be compromised by an interruption after the item had started and before it had ended. Interruptions might result from twin actions such as closing the browser, or clicking the browser's back or refresh buttons. Interruptions might also be caused by random events such as computer crash or loss of internet connection. Such events seem to have been rare. The effect of interruption was to forfeit the item with zero score. On logging in at a later time after an interrupted item, a twin would be presented with the following item of the test.

Web Test Rules

Scoring
For each of the 10 items, the correct response is given a score of 1, and any of the incorrect responses is given a score of 0. The practice item does not contribute to the scoring. The maximum total score for the test is 10.
Discontinue rule
Discontinue the test after incorrect responses (scoring zero) in any four consecutive items. This rule applies from item 1 onwards; it is therefore possible to discontinue the test after item 4 at the earliest.
Timeout rule
A timeout of 25 seconds applies to each item. After 25 seconds with no response, the item is forfeited with zero score, and a "next item" screen appears. It was possible to pause indefinitely on the "next item" screen before resuming at the next item in the test.

Dataset Item Variables

The item variables relating to this test, as listed in the table below, were generated automatically by programs on the web server. For the sake of completeness, the table also lists derived variables relating directly to this test (rckmadata1/2, rckmastat1/2, rckmatime1/2, rckmatmn1/2). Note that the dataset only includes data for completed tests. If a twin started the test but left it unfinished, then the data for that test were deleted from the dataset.

Note that the item response variables have been recoded where appropriate with values -1, -2 and -4 to denote item timeout, discontinued or interrupted respectively. See the web data cleaning page for further details. The start and end dates/times have not been retained in the dataset.

Variables	Explanation	Values
rckmadata1/2	Data flag: are test data present? [DERIVED VARIABLE]	0=no, 1=yes
rckmastat1/2	Test status: was the test completed? [DERIVED VARIABLE]	0=not started, 1=started but not finished, 2=finished successfully, 3=compromised by loss of data, 4=compromised by random responses
rckmasttm1/2	Start date and time of the test [not in dataset]	Date-time values
rckmaentm1/2	End date and time of the test [not in dataset]	Date-time values
rckmatime1/2	Time interval from start to end of the test [DERIVED VARIABLE]	Minutes (decimal values)
rckmatmn1/2	Mean item response time [DERIVED VARIABLE]	Seconds (decimal values)
rckmaXXan1/2	Test item response for item XX*	1=1A, 2=1B, 3=1C, 4=1D, 5=2A, 6=2B, 7=2C, 8=2D, 9=3A, 10=3B, 11=3C, 12=3D (response selected), -1=timed out, -2=discontinued, -4=item interrupted
rckmaXXsc1/2	Test item score for item XX*	0=incorrect, 1=correct
rckmaXXrt1/2	Test item response time for item XX*	Milliseconds (integer values)
rckmatot1/2	Test total score: total score for all 10 items	0 to 10 (integer values)
rckmatotp1/2	Test total score expressed as a percentage	0 to 100 (decimal values)

* XX denotes the item number, 01 to 10

Table of Test Items

The test items are tabulated below, for the practice item and the 10 main test items. In each case, the item number, stimulus image (maze), response options and correct response are shown. The practice item included a short sentence of instruction (shown below) but this was omitted in the main test items.