Idiosyncratic Shocks and the Role of Nonconvexities in Plant and Aggregate Investment Dynamics

We study a model of lumpy investment wherein establishments face persistent shocks to common and plant‐specific productivity, and nonconvex adjustment costs lead them to pursue generalized (S, s) investment rules. We allow persistent heterogeneity in both capital and total factor productivity alongside low‐level investments exempt from adjustment costs to develop the first model consistent with the cross‐sectional distribution of establishment investment rates. Examining the implications of lumpy investment for aggregate dynamics in this setting, we find that they remain substantial when factor supply considerations are ignored, but are quantitatively irrelevant in general equilibrium. The substantial implications of general equilibrium extend beyond the dynamics of aggregate series. While the presence of idiosyncratic shocks makes the time‐averaged distribution of plant‐level investment rates largely invariant to market‐clearing movements in real wages and interest rates, we show that the dynamics of plants' investments differ sharply in their presence. Thus, model‐based estimations of capital adjustment costs involving panel data may be quite sensitive to the assumption about equilibrium. Our analysis also offers new insights about how nonconvex adjustment costs influence investment at the plant. When establishments face idiosyncratic productivity shocks consistent with existing estimates, we find that nonconvex costs do not cause lumpy investments, but act to eliminate them.     

Women’s Strategic Responses to Intimate Partner Violence: A Study in a Rural Community of Bangladesh

The objective of this study was to explore women’s strategic responses to physical violence perpetrated by an intimate partner. Twenty women from a rural area of the Narshingdi district in the Dhaka division of Bangladesh who experienced physical violence at home participated in the study. Development of the interview protocol and data analysis were carried out by applying the consensual qualitative research (CQR) method. The results showed that several themes, such as women’s responses to intimate partner violence, arose from the data. First, coping strategies to pre‐violent events included three themes: (i) leaving the scene; (ii) trying to divert attention; and (iii) preparing to protest. Women’s strategic responses to violent events consisted of four themes: (i) leaving the scene; (ii) remaining silent or no giving response; (iii) seeking help from others; and (iv) protesting against the violence. Lastly, women’s strategic responses to post‐violent events consisted of three themes: (i) temporary abstinence; (ii) verbally abusive behavior to family members; and (iii) going to the parental home. Given the findings of this study, we conclude by suggesting that more work is needed to better understand effective strategies and to draw women to institutional services to prevent violence to a greater extent.     

Risk Analysis of a Gas-Processing Complex in India

ONGC's Hazira Gas-Processing Complex (HGPC) consists of facilities for receiving natural gas along with associated condensate from an off-shore field at a rate of 20 MMN M3 per day. After separating the condensate, which is processed in condensate fractionation units, the gas is processed through various steps to recover LPG and to reduce its dew point to less than 5 degrees C in order to make it suitable for transportation over long distances. The acid gas recovered during the gas-sweetening step is processed to obtain sulphur. The major products manufactured at HGPC therefore are lean sweet gas, LPG, NGL, and sulphur. The Oil and Natural Gas Commission awarded the assignment on Hazard Study and Risk Analysis of their Hazira Gas-Processing Complex (HGPC) to the Council of Scientific and Industrial Research (CSIR) in association with the Netherlands Organisation for Applied Scientific Research (TNO). The scope of this assignment covered a number of closely related and fully defined activities normally encountered in this type of work. Identification of hazards through the most appropriate methods, assigning frequency of occurrence of major unwanted incidents, quantification and assessment of probable damage to plant equipment, environment, human and animal life due to an unexpected event, and evaluation of various methods for reducing risk, together constituted the methodology for this assignment. Detailed recommendations aimed at reducing risk and enhancing reliability of plant and machinery were made. This article gives an overview of the assignment.     

Recurrence relations between product moments of order statistics

A general result for obtaining recurrence relations between product moments of order statistics is established and this result is used to determine the recurrence relations between product moments of some doubly truncated distributions. The examples considered are Weibull, exponential, Pareto, power function and Cauchy distributions.     

A note on the asymptotic efficiency of the sobel–wald test

Let X₁,X₂, … be iid random variables with the pdf f(x,θ)=exp(θx?b(θ)) relative to a σ-finite measure μ, and consider the problem of deciding among three simple hypotheses H_i:θ=θ_i (1?i?3) subject to P(acceptH_i|θ_i)=1?α (1?i?3). A procedure similar to Sobel–Wald procedure is discussed and its asymptotic efficiency as compared with the best nonsequential test is obtained by finding the limit lim_a→0(E_iN(a)/n(a)), where N (a) is the stopping time of the proposed procedure and n(a) is the sample size of the best non-sequential test. It is shown that the same asymptotic limit holds for the original Sobel–Wald procedure. Specializing to N(θ,1) distribution it is found that lim_a→0$\text{(E}{}_{\mathrm{i}}\text{N(α)/n(α))=}\text{1}\text{4}$ (i=1,2) and lim_a→0 (E₃N(α)n(α))=δ²₁/4δ, where δ_i=(θ_i+1?θ_i) with 0<δ₁?δ₂. Also, the asymptotic efficiency evaluated when the X's have an exponential distribution.     

A note on the admissibility of hammersley's estimator of an integer mean

Let X₁, X₂, …, X_n be identically, independently distributed N(i,1) random variables, where i = 0, ±1, ±2, … Hammersley (1950) showed that d = [X?_n], the nearest integer to the sample mean, is the maximum likelihood estimator of i. Khan (1973) showed that d is minimax and admissible with respect to zero-one loss. This note now proves a conjecture of Stein to the effect that in the class of integer-valued estimators d is minimax and admissible under squared-error loss.     

Caste and Muslim Peasantries of North India and East and West Pakistan

On croit généralement que l'lslamisme est une confession religieuse égalitaire et qu'il en découle que les sociétés où l'on est de cette religion n'ont pas un systéme rigide de stratification. A la suite d'une recherche effectuée auprès de paysans musulmans dans le nord de l'lnde et dans les régions orientale et occidentale du Pakistan, l'auteur indique au contraire que des classes rigides existent dans des sociétés de religion islamique. II tente de démontrer que la rigidité de cette stratification tient en partie à la tradition islamique même et pas seule-ment à rinfluence des castes hindoues.     

Forecasting demand for food in Libya—using confidence limits

Many developing countries are not self-sufficient in food production and they depend on food imports. In order to plan imports well in advance, the demand for food must be forecasted. If the forecasts are too low, the people suffer. On the other hand if the forecasts are too high—the food being a perishable commodity—resources of the country are wasted. The Food and Agricultural Organization of the United Nations (FAO) undertakes such forecasts occasionally. The FAO however links the food consumption to the income of a country and then just assume future income. Such forecasts have no scientific validity and could both fall short or be grossly excessive. In this study, the methodologies of Time Series and Regression Analysis are combined to avoid any guesses. Then confidence intervals are built so that it can be stated, e.g. with 95 per cent confidence that a nation will not eat more than the amount specified. A comparison of costs is made and it is shown that a country can save millions of dollars through the method of statistical confidence limits rather than by adding arbitrary quantities to means and averages. Finally savings possible in some other developing countries, by adopting the proposed method, are tabulated.     

Designing a control chart of extended EWMA statistic based on multiple dependent state sampling

In this paper, we presented a memory type control chart (CC) based on multiple dependent state (MDS) sampling to pinpoint the slight variation in the process mean for the quality trait of normal distribution (ND). Two pairs of control limits denominated as internal and external control limits are derived using under control mean and variance. The essential steps are taken to get the value of average run length (ARL) for stable and disturb process. Various tables of ARLs are erected using different smoothing constants, shifts and MDS parameter. Comparisons are established to assess the effectiveness of initiated CC with the various existing CC in term of ARL. It has been ascertained that offered CC manifest the best performance in searching out the diminutive changes in the process mean. Two examples, one is based on simulation study and other is related to real-life data, have been discussed for its practical purpose.KEYWORDS: Multiple dependent state, normal distribution, smoothing constants, control chart