Letter and Number Series

The 9 Letter and Number Series items prompt participants with short digit or letter sequences and ask them to identify the next position in the sequence from among six choices.


Descriptive Statistics
Item n mean sd
LN.01 31,239 0.79 0.41
LN.03 31,173 0.59 0.49
LN.05 31,486 0.75 0.43
LN.06 34,097 0.46 0.50
LN.07 36,346 0.62 0.49
LN.33 39,384 0.59 0.49
LN.34 36,655 0.62 0.48
LN.35 34,372 0.47 0.50
LN.58 39,047 0.42 0.49

Item Information Characteristics
Latent Trait Level
(normal scale)
Item -3 -2 -1 0 1 2 3
LN.01 0.11 0.30 0.45 0.29 0.10 0.03 0.01
LN.03 0.04 0.15 0.36 0.43 0.23 0.08 0.02
LN.05 0.09 0.31 0.58 0.38 0.11 0.03 0.01
LN.06 0.03 0.09 0.27 0.45 0.33 0.13 0.04
LN.07 0.03 0.17 0.69 0.74 0.20 0.03 0.01
LN.33 0.04 0.15 0.40 0.49 0.24 0.07 0.02
LN.34 0.03 0.18 0.67 0.71 0.20 0.04 0.01
LN.35 0.04 0.10 0.21 0.28 0.23 0.12 0.05
LN.58 0.01 0.05 0.26 0.76 0.55 0.14 0.02
TIF 0.42 1.51 3.89 4.54 2.21 0.66 0.17
SEM 1.55 0.82 0.51 0.47 0.67 1.24 2.41
Reliability NA 0.34 0.74 0.78 0.55 NA NA


The Letter and Number Series Items are available here.