Description of Test
The test consists of a series of general knowledge questions. For each question, there are four possible responses; the twin selects a response by clicking on it on the screen. There are 30 items: the questions and responses are tabulated below. A twin taking the test may be presented with fewer than 30 items, because of the branching and discontinue rules, which are described below.
Each item is presented in two ways: as text on the screen, and as an audio recording. The text and audio file for each item are downloaded immediately before the item is presented. The audio recording was included as an aid to any twins with reading difficulties; this test was not intended to assess reading ability in addition to general knowledge.
Test Rules
Note that this test did not have an item timeout rule.
- 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 30. - Branching rules
- Start at item 5, and proceed to item 6.
- If both items 5 and 6 are correct (scoring 1 each), give credit for items 1-4 (as though they had been answered correctly, gaining a score of 1 for each item), then proceed upwards from item 7.
- If either item 5 or item 6 is incorrect (scoring 0), attempt the
lower items (1-4) in reverse order. Then:
- If any two successive items are correct (e.g. 4 and 3), then give credit for any of items 1-4 not yet attempted; then proceed upwards from item 7. Note that if either item 5 or item 6 is correct, and this is followed by a correct answer for item 4, then this results in an upward branch to item 7 (items 5 and 4 are treated as successive items, as are items 6 and 4, for this rule).
- If no two successive items are correct, the test ends after item 1 has been attempted.
- Discontinue rules
Discontinue the test after five scores of zero in any six consecutive items. This rule applied throughout the test after five or more items had been attempted.
Item Variables
The item variables relating to the General Knowledge 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.
In most cases the values of these variables have been left unaltered, although some have been recoded during data cleaning. 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 skipped and credited due to upward branching, the item response variable is recoded from missing to -3 (the item score is already recorded as 1 on the web server).
- 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 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 start and end dates and times have not been retained in the dataset.
Variables | Explanation | Values |
---|---|---|
jgstat1/2 | Test status: outcome of test | 0=not started, 1=started but not finished, 2=successfully completed, 4=random responses |
jgdata1/2 | Data flag: is test data present in the dataset? | 0=no, 1=yes |
jgstdt1/2 | Start date of the test [not in dataset] | Date values |
jgsttm1/2 | Start time of the test [not in dataset] | Time values |
jgendd1/2 | End date of the test [not in dataset] | Date values |
jgendt1/2 | End time of the test [not in dataset] | Time values |
jgsess1/2 | Number of sessions (at the computer) used by the twin to complete the test. | Integer values of 1 or above |
jgtime1/2 | Time taken to complete the test, in seconds | Integer values (number of seconds) |
jg01a1/2 through to jg30a1/2 | Item response (see table of items below for details) | 1=A, 2=B, 3=C, 4=D. Also -2=discontinued, -3=credited due to upward branching, -4=item crashed. |
jg01s1/2 through to jg30s1/2 | Item score (see table of items below for details) | 0=incorrect, 1=correct |
jg01at1/2 through to jg30at1/2 | Answer time: length of time (in seconds) taken by the twin to respond to this item | Integer values (number of seconds) |
jg01dt1/2 through to jg30dt1/2 | 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 | Integer values (number of seconds) |
jg01o1/2 through to jg30o1/2 | Order or sequence of this item in the test; dependent on the branching path taken by the twin through this test | Integer values of 1 or above |
Test Items
The numbering of the items, shown in the table below, equates to the numbering used in the item variables. Note that this is not the same as the order in which items were presented to twins in the test (see branching rules above).
item | question | response A | response B | response C | response D | correct response |
---|---|---|---|---|---|---|
1 | What do you call this? | Neck | Toes | Eyes | Nose | D |
2 | How many ears do you have? | 1 | 2 | 3 | 4 | B |
3 | How many legs does a dog have? | 2 | 3 | 4 | 5 | C |
4 | What is the day that comes after Thursday? | Monday | Tuesday | Wednesday | Friday | D |
5 | What must you do to make water boil? | Heat it | Put water in it | Put eggs in | Stir it | A |
6 | Name two kinds of coins | French and German | Pound and Penny | Queen and Flower | Money and Five Pound Note | B |
7 | What month comes right after March? | April | May | June | February | A |
8 | How many days are there in a week? | 2 | 5 | 7 | 10 | C |
9 | What are the four seasons of the year? | Summer, Autumn, Winter, Spring | Halloween, Mother’s Day, Christmas, Easter | Sunny, Rainy, Windy, Snowy | Hot, Warm, Cool, Cold | A |
10 | How many things make a dozen? | Six | Twelve | Eggs | Ten | B |
11 | How many hours are there in a day? | 8 | 12 | 24 | 60 | C |
12 | What does the stomach do? | Digests food | Growls | Breathes | Swallows | A |
13 | Who was Christopher Columbus? | He was president | He was a pilgrim | He discovered America | He was an inventor | C |
14 | Name three oceans | Salt Lake, Nile, Gulf of Mexico | River, Lake, Sea | Indian, Pacific, Atlantic | Stream, Pond, Creek | C |
15 | Which month has one extra day every four years? | January | February | May | December | B |
16 | In what direction does the sun set? | North | East | South | West | D |
17 | How is oxygen returned to the air? | By breathing | By plants | By the wind | By clouds | B |
18 | On what continent is Brazil? | South Africa | Asia | South America | Europe | C |
19 | What is water made of? | Hydrogen and oxygen | Rain | Helium and oxygen | Minerals and chemicals | A |
20 | Who invented the electric light bulb? | Albert Einstein | Thomas Edison | Benjamin Franklin | Thomas Jefferson | B |
21 | What country in the world has the largest population? | Africa | Russia | New York | China | D |
22 | Who was Anne Frank? | A singer | A pilot | A girl who wrote a diary | A teacher of deaf and blind | C |
23 | What are hieroglyphics? | Ancient Greek letters | Roman numerals | Egyptian picture writing | Cave paintings | C |
24 | What is the main material used to make glass? | Plastic | Sand | Hydrogen | Fibreglass | B |
25 | What is the capital of Greece? | Rome | Cairo | Crete | Athens | D |
26 | What causes iron to rust? | Acid | Oxygen | Salt | Minerals | B |
27 | What is a barometer? | It measures rainfall | It measures wind speed | It measures air pressure | It measures earthquakes | C |
28 | Who was Charles Darwin? | He was a poet | He discovered the structure of DNA | He was a character in a Dickens novel | He developed the theory of evolution | D |
29 | How far is it from London to New York? | 200 miles | 3,000 miles | 9,000 miles | 40,000 miles | B |
30 | What does turpentine come from? | Conifer trees | Varnish | Acid | Ethyl Alcohol | A |