Lars R. Bergman

EXACON: A Fortran 77 Program for the Exact Analysis of Single Cells in a Contingency Table:

A program named EXACON is presented which performs exact cellwise analyses of two-way contingency tables. EXACON is written in FORTRAN 77 and is interactive. One-tailed probabilities are computed for the observed frequency of each cell according to two different probability models, one being Fishers exact test for a 2 x 2 table. Despite the fact that exact probabilities are computed, EXACON does not demand much computer time even for fairly large samples.

A Person Approach in Research on Adolescence Some Methodological Challenges

Research on adolescence has to face a number of methodological challenges, which tend to be particularly relevant for studies concerning this period of life. Some of these issues are addressed in this article. First, a metatheoretical perspective is introduced in the form of the person approach, which is based on the holistic-interactionistic research paradigm. In a person approach the individual as a “functioning whole” is central and not the variable, as is the usual case. This perspective has consequences both for the theoretical thinking and for the methodological approach. A short overview is given of major types of pattern-based methods often used for carrying out a person approach. Against this background, some methodological challenges for research on adolescence are discussed: Studying growth in patterns or configurations, interindividual differences in maturational tempo, a dynamic versus a static perspective, and prediction and explanation.

Studying Individual Patterns of Development Using I‐States as Objects Analysis (ISOA)

An approach is presented for studying individual pattern development in person-oriented terms focusing on the concept of i-state, i.e. an individuals configuration of information at a specific point in time. The procedure is called I-States as Objects Analysis (ISOA). First common i-states (typical states) are identified using cluster analysis of subindividuals and then this information is used for describing typical developmental patterns. Both a general procedure and a specific procedure used on a demonstration data set were developed. Using ISOA, change and stability can be studied both with regard to structure and with regard to individual variation. An empirical example was given which concerned longitudinal data about school grades at four different ages for 333 boys and girls. The data were split into a test sample and a replication sample of equal sizes. It was contended from the empirical study that ISOA functioned reasonably well on the sample studied. In the discussion, it was pointed out that ISOA can be a powerful method to use for small samples with many measurement occasions and that the method is optimal for studying short-term change.

Development of adjustment problems in girls: what syndromes emerge?

The development of a broad spectrum of adjustment problems in girls was studied longitudinally from late childhood to early adulthood. A specific interest concerned how well the externalizing-internalizing distinction could explain the data. The sample consisted of about 500 Swedish girls, reasonably representative of the general population. Variable-oriented methods were complemented with person-oriented methods to study syndrome formation at the level of the individual. The results suggested a rather diversified pattern of multi-problem syndromes in late childhood, whereas the syndrome structure in early adolescence was organized around a differentiation between girls with externalizing adjustment problems and girls with peer problems. An externalizing syndrome was found to be stable between late childhood and early adolescence, increasing the risk of severe maladjustment in adulthood. Internalizing problems showed no clear-cut continuity with adult maladjustment. Results are discussed in relation to the externalizing-internalizing distinction, which to some extent is called in question.

Conceptual and methodological considerations in a developmental approach to the study of positive adaptation

This paper addresses conceptual and methodological issues in formulating a developmental approach to studying positive adaptation. A general definition of positive adaptation is put forth involving the assessment of developmental processes by which individuals attain unusually favorable adjustment patterns, given their background and available resources. Conceptual issues related to this definition are discussed including the need to assess positive functioning on a relative basis according to individual differences in developmental circumstances. The necessity for longitudinal investigation of the emergence and maintenance of positive adaptation in terms of an individuals total functioning is described. Methodological issues pertaining to the measurement and analysis of positive adaptation are outlined with reference to the developmental approach presented.

Child personality characteristics and selection into long-term unemployment in Finnish and Swedish longitudinal samples

The main aim of the present study was to test a model of selection into long-term unemployment obtained for a sample of 36-year-old Finns (Kokko, Pulkkinen, & Puustinen, 2000) to see whether it similarly explained long-term unemployment among 26- to 27-year-old Finns and Swedes. The participants were drawn from two ongoing longitudinal studies: the Jyväskylä Longitudinal Study of Personality and Social Development (conducted in Finland) and the Individual Development and Adaptation study (conducted in Sweden). At both ages, that is 36 and 26–27, low education was related to long-term unemployment, and explained by personality characteristics in middle childhood, such as low self-control of emotions or conduct problems, and behavioural inhibition or timidity. However, while low self-control of emotions additionally explained long-term unemployment among the 36-year-olds directly, in both the young samples personality characteristics showed only indirect effects through poor educational attainment. At age 26–27, childhood personality characteristics explained selection onto an educational track rather than selection into long-term unemployment, and length of education explained duration of unemployment.

Studying individual aging in an interindividual context : typical paths of age-related, dementia-related, and mortality-related cognitive development in old age

This study has 2 objectives: (a) to explore typical paths of cognitive development associated with aging, terminal decline, and dementia and (b) to promote and illustrate an individual-oriented approach to the study of cognitive aging based on longitudinal panel data from a population-based sample (N = 500; age range-sub(T1)= 60-80, where T refers to time) tested at 3 occasions 5 years apart. Results document interindividual differences in multivariate patterns of change. Although cognitive changes generally covary, the present study indicates that subgroups of individuals develop along different paths characterized by selective changes in subsets of cognitive functions. Typical progression of dementia followed a developmental cascade from low declarative memory, via low functioning across all observed cognitive measures, to dementia diagnosis, and finally, death.

Developmental Processes and the Modern Typological Perspective

Within the general theoretical framework of the holistic-interactionistic paradigm, the need for using methods reflecting the process characteristics of a developmental study is emphasized and certain limitations of current research practice in this regard are pointed out. We focus on a person-oriented approach that can be regarded as a modern typological approach, where patterns of values in relevant variables describing the individual are regarded as indivisible, so that the variable has a meaning only as a part of such a pattern. It is claimed that such an approach can be more process-oriented and more compatible with the holistic-interactionistic paradigm than conventional methods. Some relevant classification-based methods are briefly reviewed, and a new method (TYFO) is presented that aims at finding typical developmental patterns in data without striving for a complete classification. The procedure is illustrated with an empirical example.

Patterns of adjustment problems and alcohol abuse in early adulthood: A prospective longitudinal study

This study focuses on the importance of patterns of adjustment problems in early adolescence and convictions for alcohol abuse in the mid-teens for the development of alcohol abuse manifested in early adulthood. The study was performed on a large and representative cohort of Swedish males, prospectively followed from age 13 to age 25. A person approach was applied in which the individuals and individual patterns of adjustment problems were the objects of interest, not single variables per se. The results showed that patterns of multiple adjustment problems in early adolescence, as well as convictions for alcohol abuse in the mid-teens, significantly increased the risk for later alcohol abuse. Among multiproblem boys also convicted for alcohol abuse in their mid-teens, 72% were registered for alcohol abuse at ages 18–24. However, early single adjustment problems did not significantly increase the risk for later alcohol abuse. The importance of studying the background of alcohol abuse from a developmental and interactionistic perspective was emphasized.

On the utility of Moffitt’s typology trajectories in long-term perspective

We used a prospective longitudinal study to examine the utility of Moffitt’s (1993) trajectories of antisocial behaviour. Data on registered criminality in three time periods — before age 15 (childhood), from 15 to 20 (adolescence) and from 21 to 35 (adulthood) — were used to construct life-course trajectories of offending for males. Life-course-persistent and adolescence-limited groups were found. The life-course-persistent males had the most problematic upbringing conditions, school problems and adjustment difficulties in adolescence, and the highest social and mental health problems in middle age. Adolescence-limited offenders did not differ much from non-offenders. In these respects, Moffitt’s typology was confirmed. However, there was an equally large childhood-onset desister group. They had many of the same problems as the life-course-persistent males up to age 15, but did not differ much from the non-registered males in mid-adolescence or at the middle-age follow-up. These males are not predicted from Moffitt’s model, but cannot be ignored. There was also a group of males who started to offend in adolescence and continued in adulthood, who had about the same problematic upbringing conditions, mid-adolescent maladjustment, and middle-age social and mental health problems as the life-course-persistent group.