<P> Fluid intelligence generally correlates with measures of abstract reasoning and puzzle solving . Crystallized intelligence correlates with abilities that depend on knowledge and experience, such as vocabulary, general information, and analogies . Paul Kline identified a number of factors that shared a correlation of at least r =. 60 with Gf and Gc . Factors with median loadings of greater than 0.6 on Gf included induction, visualization, quantitative reasoning, and ideational fluency . Factors with median loadings of greater than 0.6 on Gc included verbal ability, language development, reading comprehension, sequential reasoning, and general information . It may be suggested that tests of intelligence may not be able to truly reflect levels of fluid intelligence . Some authors have suggested that unless an individual was truly interested in the problem presented, the cognitive work required may not be performed because of a lack of interest . These authors contend that a low score on tests which are intended to measure fluid intelligence may reflect more a lack of interest in the tasks rather than inability to complete the tasks successfully . </P> <P> There are various measures that assess fluid intelligence . The Cattell Culture Fair IQ test, the Raven Progressive Matrices (RPM), and the performance subscale of the WAIS are measures of Gf . The RPM is one of the most commonly used measures of fluid abilities . It is a non-verbal multiple choice test . Participants have to complete a series of drawings by identifying relevant features based on the spatial organization of an array of objects, and choosing one object that matches one or more of the identified features . This task assesses the ability to consider one or more relationships between mental representations or relational reasoning . Propositional analogies and semantic decision tasks are also used to assess relational reasoning . </P> <P> Standardized IQ tests such as those used in psychoeducational assessment also include tests of fluid intelligence . In the Woodcock - Johnson Tests of Cognitive Abilities, Gf is assessed by two tests: Concept Formation (Test 5) in the Standard Battery and Analysis Synthesis (Test 15) in the Extended Battery . On Concept Formation tasks, the individual has to apply concepts by inferring the underlying "rules" for solving visual puzzles that are presented in increasing levels of difficulty . Individuals at the preschool level have to point to a shape that is different from others in a set . As the level of difficulty increases, individuals increasingly demonstrate an understanding of what constitutes a key difference (or the "rule") for solving puzzles involving one to one comparisons, and on later items identifying common differences among a set of items . For more difficult items, individuals need to understand the concept of "and" (e.g. solution must have some of this and some of that) and the concept of "or" (e.g. to be inside a box, the item must be either this or that). The most difficult items require fluid transformations and cognitive shifting between the various types of concept puzzles that the examinee has worked with previously . </P> <P> Concept Formation tasks assess inductive reasoning ability . In the Analysis - Synthesis test, the individual has to learn and orally state the solutions to incomplete logic puzzles that mimic a miniature mathematics system . The test also contains some of the features involved in using symbolic formulations in other fields such as chemistry and logic . The individual is presented with a set of logic rules, a "key" that is used to solve the puzzles . The individual has to determine the missing colors within each of the puzzles using the key . Complex items present puzzles that require two or more sequential mental manipulations of the key to derive a final solution . Increasingly difficult items involve a mix of puzzles that require fluid shifts in deduction, logic, and inference . Analysis Synthesis tasks assess general sequential reasoning . </P>

Of intelligence are those aspects of intelligence reflecting crystalized intelligence