Can Fast and Slow Intelligence Be Differentiated?
8.4.2013
1. Introduction A popular present-day approach is to look for
pure measures of speed and power external to the test
Speed and power are different but positively correlated.
Slow responses are of a different nature than fast responses. Fast responses are based on more automatic
direct-link mediated processing while slow responses are based on repeating one's cognitive work and/or more controlled processing.
An interest in internal to the test
1.1 Fast and slow intelligence Different processes? Or different abilities? Qualitative process differences can be inferred
from the across-item pattern of difficulties, and qualitative ability differences from the across-person pattern of the latent trait values.
1.2 Aim of the study Time-homogeneity vs. time heterogeneity
Processes Abilities
Via two tasks: verbal analogy and matrices
1.3 Distinguishing between fast and slow responses Within-person split
For each person, a fast and a slow subset of items is determined.
Within-item split For each item, a fast and a slow subset of persons
in determined.
2.1 Model
2.2 Hypothesis testing 3P&3I vs 2P&3I, 3P&2I, and 2P&2I
AIC & BIC 3P&3I vs 3P&2I
LR test 3P&3I vs 2P&3I
Mixture c2 test When using the data derived from the within-
item split…
2.3 Intelligence tests2.4 Data sets Verbal analogies test
726 persons & 34 items Raven-like matrices test
503 persons & 35 items
3.1 Description of the data Response frequencies in two approaches Persons may differ more in their response
times than items do. Cronbach alpha: Fast responses were more
reliable than the slow responses.
3.2 Model comparison
Correlations between the two accuracy (q2 & q3)
Because the difficulties are fixed effects, no such correlations are available.
Estimated variances are larger for fast than slow
3.3 Correlations and variances
3.4 Additional analysis3.5 Speed and accuracy
within-item split within-person split
qg q’ 2 bg b’ 2
q1 -.184 .489 b1 .792 .736
qg .767 bg .661
within-item split within-person split
qg q’ 2 bg b’ 2
q1 -.422 -.965 b1 .630 .681
qg .646 bg .590
4. Discussion and conclusion Fast and slow intelligence can be differentiated, and
they are strongly correlated. Fast responses differentiate better than slow
responses between persons as well as items. A somewhat different kind of ability is measured for
respondents with primarily slow responses compared to the ability that is measured for respondents with primarily fast responses.
Given the higher variance of fast intelligence compared to slow intelligence, the ability of fast respondents is measured in a more reliable way than the ability of slow respondents.
Time pressure