### Instructions for Differences in Darkness

Your task is to judge the difference in darkness between the two dot patterns. Each judgment is like a subtraction problem, judging the darkness on the left minus the darkness on the right. Use the following scale:
1= pattern on the RIGHT is very much darker than pattern on the LEFT
2= pattern on the RIGHT is much darker than pattern on the LEFT
3= pattern on the RIGHT is darker than pattern on the LEFT
4= pattern on the RIGHT is slightly darker than pattern on the LEFT
5= no Difference: the patterns are equally dark
6= pattern on the LEFT is slightly darker than pattern on the RIGHT
7= pattern on the LEFT is darker than pattern on the RIGHT
8= pattern on the LEFT is much darker than pattern on the RIGHT
9= pattern on the LEFT is very much darker than pattern on the RIGHT

#### Warmup Trials for Differences in Darkness

W1. - (These two are equal, so you respond "5."

W2. - (These two are also equal.)

W3. - (Which is darker? What is the difference of LEFT minus the RIGHT?)

W4. - (Which is darker? Judge difference of LEFT minus RIGHT)

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50. What is your age? years.
51. Gender: Are you Male or Female?
Female
Male

52. How many years of Education have you completed? Put 12 for High School Diploma
Put 16 for college diploma (bachelor's degree).
put 20 for doctorate degree (Ph.D., M.D., etc).
Education:
53. Nationality (country of birth):