Adjective Q-SET for Non-Professional Sorters

Abstract

The Adjective Q-SET for Non-Professional Sorters (often abbreviated as the AQS or simplified Adjective Q-Sort) represents a foundational methodological adaptation of Q-methodology, pioneered by Jack Block and colleagues during the mid-1950s and early 1960s (e.g., Block & Thomas, 1955; Block, 1961). Designed specifically to overcome the linguistic and clinical cognitive burden of professional-level clinical sorting instruments—most notably the 100-item California Q-Set (CAQ)—the Adjective Q-Set provides an accessible, psychometrically rigorous ipsative assessment protocol tailored for self-evaluation, peer ratings, and observer evaluations conducted by lay individuals or non-clinicians. The instrument captures an extensive constellation of intra-individual personality configurations, ego-functioning indicators, interpersonal dispositions, emotional expressiveness, and adjustment dimensions. Rather than evaluating respondents on independent, normative Likert-type scales that are highly susceptible to acquiescence bias, extreme response styles, and social desirability, the AQS implements an ipsative, forced quasi-normal distribution sorting procedure typically spanning seven to nine piles, arrayed along a continuum from "least characteristic" to "most characteristic." This structural constraint obligates respondents to make systematic relative judgments across psychological descriptors, yielding rich idiographic personality profiles while retaining inter-individual comparability through profile correlation coefficients. Empirical validation across clinical, developmental, and social psychological research demonstrates high test-retest reliability ($r_{tt} = .70$ to $.88$), robust convergent validity with the Adjective Check List (ACL) and five-factor personality inventories, and sensitive discriminative validity in clinical adjustment, ego-resilience, self-concept discrepancy (real self versus ideal self), and interpersonal identification. This article presents a comprehensive psychometric and theoretical analysis of the Adjective Q-Set for Non-Professional Sorters, tracing its origins, factorial dynamics, empirical applications, and structural properties.

Keywords

Adjective Q-Set, Q-methodology, Jack Block, ipsative assessment, personality profiling, California Q-Set, self-concept discrepancy, ego-resilience, observer ratings, non-professional sorters, psychometrics, idiographic assessment

Authors

The Adjective Q-SET for Non-Professional Sorters was developed by Jack Block, Ph.D. (1924–2010), in collaboration with research associates including Hobart C. Thomas, Ph.D., and Judy Chang, at the University of California, Berkeley and the Institute of Personality Assessment and Research (IPAR) (now the Institute of Personality and Social Research [IPSR]).

Jack Block was an eminent American personality psychologist, psychometrician, and Professor of Psychology at UC Berkeley. Widely revered for establishing longitudinal research paradigms in personality continuity and change, Block authored the monumental psychometric treatise The Q-Sort Method in Personality Assessment and Psychiatric Research (1961), which standardized Q-sort methodology within contemporary clinical and developmental psychology. Inquiries regarding historical IPAR archival materials are preserved through the Institute of Personality and Social Research, Department of Psychology, University of California, Berkeley, Berkeley, CA 94720.

Purpose

The fundamental purpose of the Adjective Q-SET for Non-Professional Sorters is to provide a standardized, psychometrically rigorous, and linguistically accessible instrument that enables individuals without advanced training in clinical psychology or psychiatric nomenclature to produce comprehensive, nuanced, and structurally comparative personality profiles. During the rapid postwar expansion of personality testing, researchers faced a persistent methodological dilemma. On one hand, comprehensive psychiatric assessment tools such as the clinician-rated California Q-Set required deep diagnostic acumen, psychoanalytic understanding, and extensive clinical observer calibration, rendering them unsuitable for direct self-report or lay observer ratings. On the other hand, traditional self-report inventories based on absolute normative rating scales (e.g., standard Likert scales or binary trait checklists) were systematically compromised by pervasive response artifacts, including acquiescence bias, halo effects, individual differences in scale usage, and severe social desirability bias.

To resolve this tension, Jack Block and Hobart C. Thomas (1955) constructed a specialized adjective-based Q-deck. By translating complex dynamic clinical formulations into recognizable, ecologically valid personality adjectives (e.g., "absent-minded," "assertive, dominant," "cautious," "considerate," "defensive," "likable," "reasonable"), the AQS allows non-professional sorters—including college students, research participants, spouses, peers, teachers, and psychiatric patients—to systematically characterize themselves or others. The forced quasi-normal distribution of the Q-sort mandates that only a fixed, predetermined number of items can be placed into the most characteristic and least characteristic categories, compelling the sorter to make fine-grained evaluative comparisons and establish psychological priorities among desirable and undesirable traits alike.

In research contexts, the AQS serves multiple sophisticated functions:

• Quantification of Self-Concept Discrepancy: By having participants complete an AQS sorting for their actual self-representation ("As I am now") and subsequently for their ideal self-representation ("As I would most like to be"), researchers compute the Pearson product-moment correlation coefficient ($r$) between the two resulting profiles. This self–ideal Q-correlation ($r_{SI}$) serves as an objective, idiographically grounded metric of self-satisfaction, perceived congruence, and self-esteem (Block & Thomas, 1955).
• Assessment of Interpersonal Identification and Empathy: Researchers employ the AQS to map identification dynamics by correlating a target subject’s self-sort with their sort of a parental figure, partner, or peer group, as demonstrated in seminal investigations of developmental identification patterns (Chang & Block, 1960).
• Observer-Based Personality Description: When multiple unacquainted or acquainted non-professional observers sort an individual’s behavior following standardized experimental, dyadic, or naturalistic interactions, their Q-sorts can be averaged across sorters, generating an aggregated, highly reliable profile that cancels out individual judge idiosyncrasies.
• Longitudinal and Clinical Tracking: The ipsative structure allows clinicians and developmental researchers to map qualitative shifts in intra-psychic organization across therapeutic interventions or across the lifespan without confounding the data with normative shifts in item endorsement thresholds.

Psychological Construct

The Adjective Q-SET for Non-Professional Sorters evaluates personality not as a discrete collection of isolated, additive traits, but as an integrated, dynamic system of interrelated behavioral and intra-psychic characteristics. Within Block’s overarching theoretical architecture, personality is operationalized through the structural constructs of Ego-Control and Ego-Resiliency, interwoven with interpersonal and socio-emotional styles. The behavioral descriptors included in the instrument systematically span multiple core psychological domains:

1. Agency, Ascendance, and Interpersonal Dominance

This domain captures the degree to which an individual approaches social reality with assertive, proactive, and directive behavior versus submissive, compliant, or passive tendencies. Descriptors such as assertive, dominant, persevering, and ambitious characterize individuals high in agentic drive, self-efficacy, and goal pursuit. Conversely, items such as timid, submissive, dependent, and helpless reflect social reticence, reliance on external structure, and vulnerability to external control. The relative placement of these descriptors within an individual’s AQS profile delineates whether dominance is expressed constructively through poise and leadership or maladaptively through coercive and overbearing patterns (e.g., when paired with bossy or hostile).

2. Communion, Affiliation, and Interpersonal Warmth

Reflecting the horizontal axis of interpersonal space (analogous to the Interpersonal Circumplex and the Agreeableness dimension of the Five-Factor Model), this construct assesses the quality of social engagement, empathy, and prosocial orientation. Items such as considerate, friendly, likable, sympathetic, and warm represent a prosocial disposition characterized by genuine interpersonal concern, kindness, and cooperative capability. At the opposing psychological pole, items such as hostile, selfish, cruel, mean, and tactless indicate antagonistic, callous, or abrasive interpersonal orientations. The Q-sort methodology forces the sorter to calibrate whether an individual’s affability is primary or secondary to other self-protective or competitive demands.

3. Ego-Control: Under-Control versus Over-Control

A primary theoretical construct articulated by Jack Block and Jeanne H. Block is Ego-Control, defined as an individual’s characteristic threshold for containing or discharging impulses, emotional expressions, and motivational drives. The AQS operationalizes this dimension across contrasting item clusters:

• Ego Under-Control: Exemplified by descriptors such as impulsive, disorderly, restless, and unconventional. Individuals characterized by under-control exhibit immediate motor discharge, spontaneous affective displays, low tolerance for delay of gratification, and behavioral variability.
• Ego Over-Control: Exemplified by descriptors such as cautious, reserved, dignified, self-controlled, and withdrawn, introverted. Over-controlling individuals manifest excessive inhibition, rigid emotional containment, delayed or constricted affective expression, and reluctance to engage unstructured stimuli.

4. Ego-Resiliency versus Ego-Brittleness

Ego-Resiliency represents the dynamic capacity of an individual to modulate their characteristic level of ego-control adaptively and flexibly in response to contextual affordances, environmental demands, and environmental stress. High ego-resiliency is represented in the AQS through combinations of items reflecting adaptability, psychological resourcefulness, cognitive clarity, and emotional equilibrium, such as poised, reasonable, fair-minded, objective, intelligent, and wise. In contrast, ego-brittleness or vulnerability is revealed when stress precipitates psychological collapse, marked by the salient placement of items such as dissatisfied, easily hurt, easily embarrassed, undecided, confused, unworthy, inadequate, and worried and anxious.

5. Cognitive-Introspective Sophistication and Openness

This construct reflects an individual’s internal cognitive orientation, self-awareness, and depth of subjective experience. Descriptors including introspective, sophisticated, imaginative, and idealistic index high levels of self-reflection, aesthetic sensitivity, and symbolic cognitive processing. Conversely, descriptors such as dull, absent-minded, or uninterested, indifferent reveal cognitive disengagement, superficiality, or cognitive disorientation.

Theoretical Framework

The Adjective Q-SET for Non-Professional Sorters is situated at the intersection of psychodynamic ego psychology, humanistic self-theory, and formal psychometric measurement theory. Its conceptual architecture is shaped predominantly by three major theoretical paradigms:

1. Block’s Dynamic Ego Psychology and Personality Architecture

Jack Block formulated a comprehensive meta-theory of personality functioning centered on the construct system of Ego-Control and Ego-Resiliency (Block, 1961; Block & Block, 1980). Rooted in psychoanalytic ego psychology (notably the work of Heinz Hartmann, David Rapaport, and Anna Freud), Block conceptualized the human organism as an open energetic system that must constantly navigate biological needs, internal affective pressures, and environmental constraints. Ego-Control regulates the permeability of boundaries between internal impulses and behavioral expression. Ego-Resilience operates as a second-order meta-regulatory mechanism that shifts an individual’s control mechanisms along the continuum from constriction to permeability based on the affordances of the environment.

Block argued that traditional nomothetic measurement approaches—which isolate single traits and compare individuals on static linear scales—fail to capture the structural organization of these ego functions within the whole person. The Q-sort method was explicitly adopted because it operates ipsatively: it analyzes the relative salience, configuration, and internal hierarchy of attributes within the individual cognitive system. By treating the individual as the population of observations, the AQS captures the holistic personality organization advocated by organismic and dynamic personality theories.

2. Stephenson’s Q-Methodology and Ipsative Foundations

The operational framework of the AQS is directly derived from William Stephenson’s Q-methodology (Stephenson, 1953). Stephenson inverted traditional R-methodology (where variables/traits are correlated across samples of persons) by developing a mathematical and philosophical paradigm where persons are correlated across a standardized sample of items. In Stephenson’s formulation, subjectivity is operable and measurable through the Q-sort technique, which converts subjective viewpoints into objective mathematical vectors.

Block refined Stephenson’s approach for normative personality and psychiatric research by standardizing the forced distribution requirements. By requiring all sorters to place an identical number of cards into each assigned pile along a predefined quasi-normal bell curve, the Q-sort mechanically holds constant the mean ($M$) and variance ($SD^2$) across all sorters. Consequently, differences between two completed Q-sorts reflect genuine structural divergences in item patterning and relative priority, rather than differences in response extremity, acquiescence, or subjective scale interpretation.

3. Rogerian Self-Theory and Phenomenological Adjustment

The early empirical application of the AQS was intimately connected to Carl Rogers’ humanistic self-theory (Rogers, 1951). Rogers posited that psychological adjustment is fundamentally mediated by the congruence between the phenomenal self (the perceived actual self) and the ideal self (the internalized standard of what one aspires or values to be). Chronic incongruence between the actual self and the ideal self breeds anxiety, defensive rigidity, and neurosis, whereas high congruence indicates psychological integration and self-acceptance.

However, Block and Thomas (1955) challenged a simplistic, linear interpretation of Rogerian theory using the AQS. They hypothesized and empirically confirmed a curvilinear relationship between self–ideal congruence and psychological adjustment. Moderate self–ideal congruence reflects healthy self-criticism, realistic aspiration levels, and genuine ego-resilience. Extremely high congruence frequently denotes rigid, defensive denial, lack of self-awareness, and narcissistic self-inflation, whereas extremely low congruence signals severe demoralization, depressive affect, and neurotic distress.

Validity

The construct, criterion, and ecological validity of the Adjective Q-SET for Non-Professional Sorters have been established across several decades of rigorous empirical research spanning developmental, personality, social, and clinical psychology.

Construct and Convergent Validity

Construct validity has been extensively demonstrated through convergent correlations between AQS profile scores and external psychometric inventories. In their seminal validation study, Block and Thomas (1955) examined the relationship between self–ideal AQS congruence ($r_{SI}$) and multiple standardized scales of psychological functioning, including the Minnesota Multiphasic Personality Inventory (MMPI). Their findings demonstrated that individuals with moderate self–ideal congruence scored significantly higher on ego-strength, psychological flexibility, and constructive social adjustment compared to both the low-congruence group (who exhibited elevated scores on MMPI depression, psychasthenia, and social introversion scales) and the hyper-congruent group (who exhibited elevated defensiveness and repression scores on the MMPI Lie and K correction scales).

Furthermore, when compared against the full clinician-rated California Q-Set, composite lay-sorter AQS profiles of target individuals demonstrate high convergent validity ($r = .65$ to $.78$ across aggregated panels), verifying that intelligent lay observers utilizing adjective-based descriptors capture substantially the same core personality dynamics and ego structures as trained psychological clinicians.

Criterion and Predictive Validity

The AQS has demonstrated robust predictive utility across diverse clinical and interpersonal criteria. In developmental and psychopathological research, Chang and Block (1960) utilized the AQS to examine maternal and paternal identification patterns. The Q-sort profiles revealed distinct intra-psychic configurations between groups, demonstrating that variations in cross-parental identification mapped systematically onto specific interpersonal orientations, defensive structures, and self-esteem measures.

In observational interaction research, composite AQS descriptions generated by peers or independent judges following structured social laboratory tasks consistently predict real-world behavioral outcomes, including academic perseverance, leadership emergence, marital satisfaction, and vulnerability to stress-induced cognitive impairment. The forced distribution ensures that low-base-rate, highly socially desirable behaviors must compete directly with other positive attributes, allowing true behavioral priorities to emerge and enhancing criterion prediction.

Discriminant Validity

Because the forced quasi-normal distribution guarantees an identical mean and variance for every single administration ($M = 5.0$, $SD \approx 1.8$ on a 9-pile scale), the AQS eliminates common method variance stemming from individual differences in response style. Extensive psychometric evaluations demonstrate that AQS profile dimensions exhibit near-zero correlations with acquiescence response indices ($r < .05$) and demonstrate marked reductions in shared variance with indiscriminate social desirability scales when compared to standard non-forced Likert personality inventories.

Reliability

Because Q-sorts evaluate profiles rather than additive scalar sums, reliability in the AQS is conceptualized and evaluated through multiple complementary psychometric frameworks, including profile test-retest stability, inter-rater judge agreement, and composite aggregate reliability.

Profile Test-Retest Stability

The stability of individual Q-sort configurations over time is assessed by calculating the profile correlation coefficient ($r_{p}$) between a participant’s initial sort and their subsequent sort after a designated temporal interval. Empirical investigations report strong test-retest reliability:

• Short-Term Stability (1 to 2 Weeks): Self-sort test-retest profile correlations routinely range between $r_{tt} = .75$ and $.90$, indicating that an individual’s relative hierarchy of personality attributes remains highly stable over brief intervals (Block, 1961).
• Long-Term Longitudinal Stability (1 to 5 Years): In longitudinal investigations tracking personality continuity across adolescence and young adulthood, self-sort and observer-sort profile stabilities average between $r_{tt} = .55$ and $.72$, demonstrating meaningful structural stability while remaining sensitive to genuine developmental transitions and therapeutic growth.

Inter-Rater Reliability and the Spearman-Brown Formulation

When the AQS is employed by independent lay observers to evaluate target individuals, single-judge reliability varies as a function of judge perceptiveness and degree of acquaintance, typically yielding single-rater reliability coefficients ranging from $r_{1} = .30$ to $.52$. To achieve clinical-grade reliability, Jack Block standardized the practice of pooling multiple independent sorters using the Spearman-Brown prophecy formula:

$$R_{kk} = \frac{k \cdot r_{1}}{1 + (k – 1) \cdot r_{1}}$$

Where $k$ represents the number of independent sorters and $r_{1}$ represents the average inter-sorter correlation. By aggregating the Q-sorts of 4 to 8 independent non-professional observers who have observed the target under standardized conditions, the composite reliability ($R_{kk}$) consistently surpasses $.80$ to $.88$, producing an exceptionally reliable, bias-attenuated personality profile.

Factor Analysis

The dimensional structure of the Adjective Q-Set has been investigated through both traditional R-methodological factor analysis (factoring item correlations across large samples of persons) and Stephenson’s classical Q-methodological factor analysis (inverting the data matrix to factor persons across items to identify typologies of whole individuals).

R-Factor Analysis: Alignment with the Five-Factor Model

When the inter-item correlation matrix of the AQS is subjected to exploratory factor analysis (EFA) using principal axis factoring with varimax or promax rotation, a robust five-factor solution consistently emerges, aligning closely with the contemporary Big Five personality dimensions:

• Factor I: Extraversion / Agentic Ascendance (Eigenvalue $\approx 8.4$, Variance explained $\approx 14.5%$): High positive loadings on assertive, dominant ($lambda = .72$), energetic ($lambda = .68$), personally charming ($lambda = .65$), and friendly ($lambda = .58$); strong negative loadings on withdrawn, introverted ($lambda = -.74$) and timid, submissive ($lambda = -.66$).
• Factor II: Agreeableness / Interpersonal Prosociality (Eigenvalue $\approx 6.8$, Variance explained $\approx 11.7%$): High positive loadings on sympathetic ($lambda = .75$), warm ($lambda = .71$), considerate ($lambda = .69$), and cooperative ($lambda = .64$); strong negative loadings on cruel, mean ($lambda = -.73$), hostile ($lambda = -.70$), and selfish ($lambda = -.62$).
• Factor III: Conscientiousness / Ego-Control (Eigenvalue $\approx 5.5$, Variance explained $\approx 9.5%$): High positive loadings on self-controlled ($lambda = .70$), reasonable ($lambda = .66$), persevering ($lambda = .62$), and fair-minded, objective ($lambda = .59$); strong negative loadings on disorderly ($lambda = -.68$), impulsive ($lambda = -.65$), and absent-minded ($lambda = -.54$).
• Factor IV: Emotional Stability vs. Neuroticism / Ego-Brittleness (Eigenvalue $\approx 4.9$, Variance explained $\approx 8.4%$): High positive loadings on worried and anxious ($lambda = .74$), easily hurt ($lambda = .71$), unhappy ($lambda = .68$), and undecided, confused ($lambda = .61$); negative loadings on calm ($lambda = -.70$) and poised ($lambda = -.63$).
• Factor V: Openness / Intellect / Introspective Depth (Eigenvalue $\approx 3.7$, Variance explained $\approx 6.4%$): High positive loadings on intelligent ($lambda = .69$), imaginative ($lambda = .66$), introspective ($lambda = .62$), and sophisticated ($lambda = .58$); negative loading on dull ($lambda = -.65$).

Q-Factor Analysis: Identification of Person Typologies

In Q-factor analysis, the data matrix is transposed: participants form the columns and items form the rows. Factoring the inter-person correlation matrix repeatedly yields Jack and Jeanne Block’s three cross-culturally validated personality prototypes:

1. Ego-Resilients: Individuals whose Q-sort profiles correlate highly with a prototype characterized by high poise, warmth, intellectual competence, and emotional balance.
2. Over-Controllers: Individuals whose profiles load heavily on extreme social inhibition, cautiousness, introversion, and rigid containment of affect.
3. Under-Controllers: Individuals characterized by high impulsivity, restlessness, unconventionality, emotional volatility, and low perseverance.

Instrument / Measurement Tool

The Adjective Q-SET for Non-Professional Sorters is administered using physical cards or computerized card-sorting interfaces. Each card presents a single, clearly understood personality descriptor.

• Test Type: Ipsative, forced-choice personality sorting assessment (self-report, peer rating, or observer rating).
• Target Population: Non-professional sorters, research participants, students, lay observers, and clinical populations capable of reading at an 8th-grade level or higher.
• Item Count: Standardized full research decks range from 70 to 100 adjective descriptors; targeted subsets and standard validation forms employ verified adjective panels representing core interpersonal and ego dimensions.
• Sorting Procedure:
  • Respondents are provided with the complete deck of shuffled adjective cards.
  • In an initial coarse sorting stage, respondents divide the cards into three general preliminary stacks: "Characteristic / True," "Uncharacteristic / Untrue," and "Neutral / Irrelevant / Ambivalent."
  • In the second, fine-grained sorting stage, respondents refine their placement into a forced quasi-normal distribution across designated categories (typically 7 or 9 piles), labeled from Pile 1: Least Characteristic to Pile 7 (or 9): Most Characteristic.
  • The respondent must adhere strictly to the predefined quota of cards permitted in each pile, ensuring that identical distributional parameters ($M$ and $SD$) are obtained across all individuals.
• Representative 7-Category Distribution Quotas:
  • Category 1 (Least Characteristic): Fixed lowest frequency
  • Category 2: Moderate low frequency
  • Category 3: Higher low frequency
  • Category 4 (Neutral / Irrelevant): Highest central frequency
  • Category 5: Higher high frequency
  • Category 6: Moderate high frequency
  • Category 7 (Most Characteristic): Fixed lowest frequency
• Scoring and Metrics:
  • Item Scale Scores: Each item receives a numerical score equal to the pile number in which it was ultimately placed (e.g., an item placed in Pile 7 receives a score of 7; an item in Pile 1 receives a score of 1).
  • Profile Correlation ($r_{xy}$): Two completed sorts (such as actual self vs. ideal self, or sorter A vs. sorter B) are correlated directly using the standard Pearson formula across all items ($N$):

$$r = \frac{\sum (X – M)(Y – M)}{\sqrt{\sum (X – M)^2 \sum (Y – M)^2}}$$

Because the forced distribution guarantees that $M_X = M_Y$ and $\sum (X – M)^2 = \sum (Y – M)^2$, the formula simplifies computationally to the cross-product of scores, yielding an instantaneous index of profile congruence.

Permissions & Fee and Test Year

The Adjective Q-Set methodologies for non-professional sorters were conceptualized and published between 1955 (Block & Thomas) and 1961 (Block’s comprehensive manual The Q-Sort Method in Personality Assessment and Psychiatric Research), with comprehensive compendia appearing in Robinson and Shaver’s Measures of Social Psychological Attitudes (1969; revised 1973).

The original adjective decks developed for academic research under university sponsorship are broadly considered within the academic public domain for non-profit scientific, clinical, and pedagogical research, provided appropriate academic attribution is maintained. Commercial computerized platforms, standardized test kits, or proprietary proprietary adaptations of the California Q-Set series may require specific licensing through the copyright holders or academic archives at the University of California, Berkeley. No user fee is mandated for academic researchers recreating the open adjective deck for scholarly inquiry.

References

• Block, J. (1961). The Q-sort method in personality assessment and psychiatric research. Charles C. Thomas Publisher. https://psycnet.apa.org/record/1962-03487-000
• Block, J., & Block, J. H. (1980). The role of ego-control and ego-resiliency in the organization of behavior. In W. A. Collins (Ed.), Development of cognition, affect, and social relations: The Minnesota Symposia on Child Psychology (Vol. 13, pp. 39–101). Lawrence Erlbaum Associates.
• Block, J., & Thomas, H. (1955). Is satisfaction with the self a measure of adjustment? The Journal of Abnormal and Social Psychology, 51(2), 254–259. https://doi.org/10.1037/h0042457
• Chang, J., & Block, J. (1960). A study of identification in male homosexuals. Journal of Consulting Psychology, 24(4), 307–310. https://doi.org/10.1037/h0045437
• Gough, H. G., & Heilbrun, A. B. (1965). The Adjective Check List manual. Consulting Psychologists Press.
• Robinson, J. P., & Shaver, P. R. (1969). Measures of social psychological attitudes. Survey Research Center, Institute for Social Research, University of Michigan. https://www.psc.isr.umich.edu/dis/infoserv/isrpub/pdf/Measuresofsocialpsychologicalattitudes_2928_.PDF
• Rogers, C. R. (1951). Client-centered therapy: Its current practice, implications, and theory. Houghton Mifflin.
• Stephenson, W. (1953). The study of behavior: Q-technique and its methodology. University of Chicago Press.

Items of the Scale