The development of an innovation: the case of porvair

Economists and management “scientists” tend to adopt a rationalistic, “black box” approach to the treatment of technological innovation, with decisions to invest in innovation being viewed as climactic acts and with the significant impact of risk and uncertainty often being disregarded. This paper examines an alternative analytical perspective: that a least the early development of technological innovation is a process of incremental decision making where managerial responses are affected by the consequences of previous decisions and by alterations in external information. The development of the “poromeric” Porvair discussed here illustrates the considerable risks that have to be borne when undertaking radical innovation, and the nature of the uncertainties, the interdependency between them and the manner in which they persist, in this case even beyond the commercialization of the new product.     

Developmental priority of identity conservation: acceleration of identity and equivalence in normal and moderately retarded children

In an attempt to clarify the chronological relationship between identity and equivalence conservation, normal preschool-aged children (experiment 1) were exposed to brief videotape demonstrations of a model conserving identity and equivalence, identity only, equivalence only, or neither. Subsequent performances indicate that identity was easier to accelerate than equivalence, and training in both identity and equivalence appeared to be most effective in accelerating conservation. Trainable mentally retarded (TMR) children were then exposed to either the identity-equivalence-conserving or control model (experiment 2). This population, which some have argued remains at a preoperational level of functioning, was more likely to conserve identity than equivalence. In addition, conservation in the training group increased following training, though these gains were not maintained over a 3-week retention interval.     

The alpha and split-half reliability of the teacher stress inventory

The internal consistency and split-half reliability of the Teacher Stress Inventory (TSI) was investigated based on data provided by 3,478 teachers, representing 22 individual and two aggregate samples from six states. The data indicate for both the strength and frequency dimensions that the TSI is highly reliable in terms of both its regular and short-form length, and that the two short forms are highly correlated with one another.     

Correlations between the stanford-binet: Fourth edition and the WISC-R with a learning disabled population

The Fourth Edition of the Stanford-Binet and the WISC-R were compared as instruments for assessing the intellectual strengths and weaknesses of students classified as learning disabled in the primary and secondary grades. Results found only a 3.28-point difference (p≥.0001) between the S-B Composite score and the WISC-R Full Scale score. Correlations between the four broad areas of the S-B and the three scales of the WISC-R ranged from .494 (S-B Abstract/Visual Reasoning with WISC-R Verbal) to .920 (S-B Composite with WISC-R Full Scale). All correlations were found to be significant. Implications of the research findings were discussed.     

Alternate-forms and alpha reliability of the Teacher Stress Inventory

The alternate-forms and alpha reliabilities of the Teacher Stress Inventory were investigated based on the responses of two groups of 138 teachers. Reliability estimates ranged from .43 to .94 for the TSI subscales and .71 to .94 for the TSI whole scale, indicating high stability and equivalence for the stress factors across immediate, one-day, one-week, and two-week intervals using two different TSI short forms. Between-forms correlations were larger for the immediate sample than they were for the interval samples. Short-form TSI alphas ranged from .76 to .90.