Cumulative correspondence analysis of ordered categorical data from industrial experiments

Most studies of quality improvement deal with ordered categorical data from industrial experiments. Accounting for the ordering of such data plays an important role in effectively determining the optimal factor level of combination. This paper utilizes the correspondence analysis to develop a procedure to improve the ordered categorical response in a multifactor state system based on Taguchi's statistic. Users may find the proposed procedure in this paper to be attractive because we suggest a simple and also popular statistical tool for graphically identifying the really important factors and determining the levels to improve process quality. A case study for optimizing the polysilicon deposition process in a very large-scale integrated circuit is provided to demonstrate the effectiveness of the proposed procedure.     

Choosing monetary sequences: theory and experimental evidence

We formulate and investigate experimentally a model of how individuals choose between time sequences of monetary outcomes. The model assumes that a decision maker uses, sequentially, two criteria to screen options. Each criterion only permits a decision between some pairs of options, while the other options are incomparable according to that criterion. When the first criterion is not decisive, the decision maker resorts to the second criterion to select an alternative. We find that: (1) traditional economic models based on discounting alone cannot explain a significant (almost 30%) proportion of the data no matter how much variability in the discount functions is allowed; (2) our model, despite considering only a specific (exponential) form of discounting, can explain the data much better solely thanks to the use of the secondary criterion; (3) our model explains certain specific patterns in the choices of the “irrational” people. We reject the hypothesis that anomalous behavior is due simply to random “mistakes” around the basic predictions of discounting theories: deviations are not random and there are clear systematic patterns of association between “irrational” choices.     

Measures of Association and Visualization of Log Odds Ratio Structure for a Two Way Contingency Table

The odds ratio (OR) is a measure of association used for analysing an I × J contingency table. The total number of ORs to check grows with I and J. Several statistical methods have been developed for summarising them. These methods begin from two different starting points, the I × J contingency table and the two‐way table composed by the ORs. In this paper we focus our attention on the relationship between these methods and point out that, for an exhaustive analysis of association through log ORs, it is necessary to consider all the outcomes of these methods. We also introduce some new methodological and graphical features. In order to illustrate previously used methodologies, we consider a data table of the cross‐classification of the colour of eyes and hair of 5387 children from Scotland. We point out how, through the log OR analysis, it is possible to extract useful information about the association between variables.     

Public Health Institutions,Clinical Research and Protection System of Patients’ Rights: An Impact Evaluation of Public Policy

Public health institutions are involved in human experimentations, which is a specific phase of pharmaceutical industry’s production process. These medical centers collect clinical evidence about experimental treatments and, at the same time, they have to guarantee patients’ safety through appropriate Institutional Review Boards. Taking human experimentation into account, this work aims at estimating a public policy designed to reduce transaction costs that are related to the protection system of patients’ rights, with both a normative and positive approach. On the one hand, considering a sample of European countries as counterfactual, an empirical analysis is performed in order to estimate the impact of a national law aimed at harmonizing the procedure to obtain opinions on clinical trials. On the other hand, an alternative law, which might be able to favor the exchange between pharmaceutical companies and patients, is proposed.     

A DIRECT TEST OF THE BUFFER‐STOCK MODEL OF SAVING

Recent models with liquidity constraints and impatience emphasize that consumers use savings to buffer income fluctuations. When wealth is below anoptimal target, consumers try to increase their buffer stock of wealth by saving more. When it is above target, they increase consumption. This important implication of the buffer stock model of saving has not been subject to direct empirical testing. We derive from the model an appropriate theoretical restriction and test it using data on working‐age individuals drawn from the 2002 and 2004 Italian Surveys of Household Income and Wealth. One of the most appealing features of the survey is that it has data on the amount of wealth held for precautionary purposes, which we interpret as target wealth in a buffer stock model. The test results do not support buffer stock behavior, even among population groups that are more likely, a priori, to display such behavior. The saving behavior of young households is instead consistent with models in which impatience, relative to prudence, is not as high as in buffer stock models. (JEL: D91)     

On the usefulness of government spending in the EU area

This paper investigates the effects of government spending on private consumption and investment in the European Union (EU). A certain consensus has been reached on the expansionary Keynesian effects of fiscal impulses on the economic activity. However, the existing empirical literature has concentrated on few countries, mostly outside the EU. We check the validity of this result for the EU area using annual data and a panel vector auto-regression approach, with particular attention being paid to robustness across alternative identification assumptions based on Cholesky orderings. Our results show that shocks to public spending positively affect private consumption and investment. According to our baseline estimate, a 1% increase in public current expenditure produces a 0.24% impact rise in private consumption, and a 0.41% impact rise in private investment. The effects are substantial, and die out slowly in the case of private consumption (the cumulative impact amounts to +0.56% after 3 years), but much faster in the case of private investment. A further disaggregation between wage and non-wage components reveals that public salaries have a relatively stronger stimulating role. This is not due to the different weights on GDP of the two components, which have comparable values in our sample.     

ANOTHER STEP IN THE STUDY OF RACE RELATIONS

Recent qualitative researchers have argued the need for a more sensitizing approach to race research that elevates in importance the concerns and interests of those under study. This article illustrates how Herbert Blumer's work on race relations, critical race theory, and participatory action research may help this objective. These projects' similar epistemologies advance a type of social imagery that has powerful emancipatory implications in regard to racial oppression. Simply put, dominant renditions of social reality–including structural imperatives and racial identities–are illustrated to be socially constructed and hence open to negotiation. As a result of this shift, sensitizing methodologies (e.g., storytelling and collaboration) are employed that allow minorities an opportunity for self-representation. The liberating potential of all these projects can be further enhanced by relating their conceptual links to recent developments in contemporary social theory. Specifically, the typical concerns with process, interaction, and experiential meanings are intersubjectively mediated and not reducible to an objective subjective theoretical framework. Rather than simply personal or external, all knowledge is recognized to be fluid and coproduced. By grounding research on this intersubjective region, equitable exchanges are possible.