Ultimate capacity of blast loaded structures common to chemical plants

There has been a great deal of investment in development of design criteria and design and construction of heavily reinforced, blast-resistant control rooms. This remains the best option for protective construction against severe blast loading experienced close in to a vapor cloud or other explosion hazard. However, most structures encountered at chemical plants and contemplated for future construction are conventional steel frame, metal clad buildings. In this paper we look closely at the response of such buildings to explosion loads and their ability to undergo large deformations without structural failure. The types of structural elements evaluated include metal decking of various gauge and shape along with a variety of girt and purlin sections. Building frames or bents are also evaluated, although the date base for these is much more limited. The work is based on observations made during investigations of large explosion accidents along with analytical predictions and test measurements. To conclude, we offer specific design criteria and connection recommendations for enhancing the overall strength of a building through the use of conventional components in unconventional construction.     

Determinants of retirement planning behaviour and differences by age

This paper presents the results of an investigation into the determinants of retirement planning behaviour and differences among three age groups: 21‐ to 39‐year‐olds, 40‐ to 59‐year‐olds and those aged 60 years and older. A national survey of 911 individuals from households with incomes of $75 000 or greater was conducted in the US. The significance of socio‐demographic variables, the ability to recover from loss, behavioural tendencies and perceived or actual personal control were investigated; together with their role in the prediction of maximization of retirement contributions and ownership in the personal individual retirement account (IRA) or Keogh accounts. The results identified several significant variables in the prediction of ownership in a personal IRA or Keogh, including age, sources of financial information, being an early investor and investor activity. The results also identified several significant variables in the prediction of the maximization of retirement contributions, including employment, income, savings activity, ex ante research, review of investment performance, early investor, investor activity, such as planning for financial future, setting up automatic deposits and reviewing financial information in the mail.     

Generalized method of moments specification testing

This paper analyzes the asymptotic power properties of specification tests which are based on a finite set of moment conditions. It shows that any such test may fail against general misspecification that causes estimator inconsistency. The mutual asymptotic equivalence of maximal degree of freedom tests is shown and the form of optimal tests against specific forms of misspecification is derived. Applications to testing for exogeneity of a set of instrumental variables are presented.     

An examination of residential mobility through the use of the log-linear model: Part II. Empirical illustrations

The theory proposed in ‘An Examination of Residential Mobility Through The Use of The Log- Linear Model, Part I’, Regional Science and Urban Economics (1978) Vol. 8, No. 2, is illustrated by analysing data obtained on moving households in an urban area.     

Estimating demand elasticities under rationing

Eliminating rationing in the United Kingdom following the Second World War was a concern for policy-makers because of potentially large fluctuations in post-war prices and the impact on unrationed goods. This study shows that in using virtual prices, elasticities can be estimated from a ‘free’ demand system consistent with observed consumer choices. Substitution estimates without accounting for rationing are misleading. In contrast, using virtual prices and estimating a ‘free’ market system yield results similar to those of the pre-war period. Results show that food rationing affected expenditure across unrationed goods. Rationing on other services had little effect on expenditure across unrationed goods.     

A nonparametric test of weak separability and consumer preferences

Two stochastic nonparametric procedures are developed to evaluate the significance of violations of weak separability. When the data have measurement error, we show that the necessary and sufficient weak separability conditions of Varian [Varian, H., 1983. Nonparametric tests of consumer behavior. Review of Economic Studies 50, 99–110] must also satisfy the Afriat inequalities. The tests detect weak separability with high probability for weakly separable data. In addition, the procedures correctly reject weak separability for both nonseparable and random utility simulated data sets. The tests also fail to reject weak separability for a monetary and consumption data set which suggests that measurement error may be the source of the observed violations.