a deterministic inventory model for deteriorating items with stock dependent demand rate abstract a deterministic inventory model is developed by assuming that the demand rate is stock dependent and the items deteriorate at a constant rate the expression for the average net profit over one production run is derived and its optimization with respect to the decision variables q initial stock and t duration of a production cycle is carried out this leads to two highly nonlinear equations which are solved by using a subroutine neqnf in imsl math library in cyber 180 480a computer system the optimal solution so derived is compared with that for the no deterioration 0 case sensitivity of the optimal solution to changes in parameter values is examined several aspects of the functional form for the demand rate are considered in a separate section finally the salient features of the problem and its solution are discussed in brief

marriage bequest and assortative matching in rural ethiopia abstract this article examines the determinants of human and physical capital at marriage using detailed data from rural ethiopia we find that assets brought to marriage are distributed in a highly unequal manner for first unions assets brought to marriage are positively associated with parents wealth indicating that a bequest motive affects assets at marriage parental wealth affects the inheritance of neither groom nor bride sibling competition from brothers affects grooms inheritance but sisters have no effect the marriage market is a major conduit for rural and gender inequality although avenues do exist for couples to accumulate wealth over their life cycle

an economic lot size model with non linear holding cost hinging on time and quantity abstract this paper develops an economic lot size inventory model where the demand rate depends on the stock level and the cumulative holding cost is non linear on both the quantity and the time they are stored more concretely it is supposed that the demand rate is a concave potential function of the inventory level and the holding cost is potential on both time and quantity moreover shortages are not allowed a general procedure to determine the optimal lot size and the maximum inventory profit is developed also some results about the profitability of the inventory system are presented this work extends several inventory models previously considered in the literature finally numerical examples which help us to understand the theoretical results are also given

beyond death do us part the long term implications of divorce perceptions on women s well being and child schooling in rural ethiopia summary this paper examines how women s perception of the division of household assets upon divorce affects women s well being and child schooling outcomes in rural ethiopia findings suggest that women who perceive that their husband would get all the assets in case of a divorce also tend to perceive less control over their lives implications of perceptions of unequal divorce allocations on child schooling are more striking not only do children in households where perceived divorce allocations favor the husband do worse compared to children of the same age but girls fare even worse than boys in these households

an eoq model with stock dependent demand shortage inflation and time discounting abstract this paper develops a finite time horizon deterministic economic order quantity eoq inventory model with shortages where the demand rate at any instant depends on the on hand inventory stock level at that instant the effects of inflation and the time value of money are taken into account considering two separate inflation rates namely the internal company inflation rate and the external general economy inflation rate the results are discussed with a numerical example and particular case of the model is discussed in brief a sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out

inventory model with stock level dependent demand rate and variable holding cost inventory models in which the demand rate depends on the inventory level are based on the common real life observation that greater product availability tends to stimulate more sales previous models incorporating inventory level dependent demand rate assume that the holding cost is constant for the entire inventory cycle this paper considers the inventory policy for an item with a stock level dependent demand rate and a storage time dependent holding cost the holding cost per unit of the item per unit time is assumed to be an increasing function of the time spent in storage two time dependent holding cost step functions are considered retroactive holding cost increase and incremental holding cost increase procedures are developed for determining the optimal order quantity and the optimal cycle time for both cost structures

union effects on wage dispersion in canadian industry abstract this paper analyzes the effects that unions have on the dispersion of wages in canada the empirical results indicate that unions have a significant effect in reducing wage dispersion the standard deviation in hourly wages is smaller for unionized workers than it is for non unionized workers this result holds not only for the more general case but also for narrowly defined demographic industrial and occupational categories finally regression estimates indicate that the coefficients on the wage determining variables are smaller in the unionized sector

intergenerational transfers in philippine rice villages gender differences in traditional inheritance customs abstract this paper examines education land and nonland asset transfers from parents to children in five rice villages in the philippines a model with family fixed effects explains transfers better than either individual heterogeneity or observed parent and child characteristics without family fixed effects families facing different land constraints exhibit significantly different patterns of educational investment in children in a subsample with completed inheritance daughters receive less education land and total inheritance but are compensated with nonland assets parents also exhibit preferential behavior towards children of the same gender daughters of better educated mothers receive more land nonland assets and total inheritance better educated fathers give land preferentially to sons but favor daughters in education

rising u s earnings inequality and family labor supply the covariance structure of intrafamily earnings this paper studies the labor supply contributions to individual and family earnings inequality during the period of rising wage inequality in the early 1980 s working couples have positively correlated labor market outcomes which are almost entirely attributable to permanent factors an intertemporal family labor supply model with this feature is used to estimate labor supply elasticities for husbands of 0 05 and wives of 0 40 this implies that labor supply explains little of the rising annual earnings inequality for married men but over 20 percent of the rise in family inequality and 50 percent of the modest rise in female inequality

control and ownership of assets within rural ethiopian households this article investigates how the control and devolution of productive assets are allocated among husband and wife theory predicts that bargaining power within marriage depends on the division of assets upon divorce and on control over assets during marriage using detailed household data from rural ethiopia we show that assets brought to marriage ownership of assets control within marriage and disposition upon death or divorce are only partly related productive resources are controlled by the household head disposition upon death or divorce only loosely depends on individual ownership during marriage but control is associated with larger claims upon divorce assets brought into marriage have little impact on disposition upon death but matter in case of divorce

some results for inventory models having inventory level dependent demand rate abstract this paper considers the inventory level dependent demand rate situation in generalized eoq models an interesting result linking the total inventory cost and the optimal policy for such a frame work is obtained and is shown to be consistent for all the models discussed in the paper

cash crops and food security evidence from ethiopian smallholder coffee producers one of the central questions in food policy debates has been the role of cash cropping for achieving food security in low income countries we revisit this question in the context of smallholder co

schooling search and spouse selection testing economic theories of marriage and household behavior the implications of the economic theories of marriage and of household fertility behavior are tested in a framework in which educational investment marital search and marital matches are responsive to marriage market conditions and the personal traits of individual agents some of which are unobserved by the econometrician implications are also derived and tested for the effects of longevity attractiveness preferences and labor and marriage market conditions on schooling marriage age and spouse choice the empirical results indicate that inattention to heterogeneity and martial selection leads to a false rejection of the economic theory of marriage but to a false acceptance of the value of time fertility hypothesis

contractual wages and the wage cushion under different bargaining settings how does a typically european bargaining system with collective bargaining and national minimum wage coexist with low unemployment and high wage flexibility a unique data set on workers firms and collective bargaining contracts in portugal is used to analyze the determinants of both the contractual wage and the wage cushion difference between contractual and actual wages the results indicate that the wage cushion stretches the returns to worker and firm attributes whereas it shrinks the returns to union power therefore firm specific arrangements partly offset collective bargaining granting firms certain freedom when setting wages contractual wages reflect trade unions egalitarian policy

haddad lawrence john hoddinott and harold alderman eds intrahousehold resource allocation in developing countries models methods and policy baltimore md johns hopkins university press 1997 384 pp 55 00 in this volume economists demographers sociologists and anthropologists collaborate in the study of how resources are allocated within households in developing countries and why it matters from a policy perspective surveying a broad range of theory and evidence the contributors examine the many social and cultural factors that influence decisions about the family and household level about the allocation of time income assets and other resources ths contributors show that a more complete understanding of intrahousehold behaviour can increase the likelihood that policies will reach the people they are intended to affect

the rising price of husbands a hedonic analysis of dowry increases in rural india dowries in south asia have steadily risen over the last 40 years and now often amount to over 50 percent of a household s assets this paper attempts to investigate the reasons behind this increase it adapts rosen s implicit market model to the indian marriage market and tests predictions from the model with data from six villages in south central india and from the indian census it is found that a marriage squeeze caused by population growth resulting in larger younger cohorts and hence a surplus of women in the marriage market has played a significant role in the rise in dowries

crop choice school participation and child labor in developing countries cotton expansion in burkina faso we estimate the effects of changes in cotton adoption on children s schooling and child labor in rural burkina faso using time and spatial variations we find evidence that expansion of cotton farming has led to an increase in enrollment and to a reduction of participation in child labor for girls there are however no detectable effects on boys in theory cotton adoption could increase household income leading to increased demand for schooling and reduced child labor on the other hand because children are productive on cotton farms adoption of cotton could increase the opportunity cost of child time and the demand for child labor we provide suggestive evidence showing that boys are more productive than girls on cotton farms taken together the results suggest that the income effect from cotton adoption might have been larger than the wage effect for girls hence the overall positive impacts on school enrollment for girls

an extension of inventory models with discretely variable holding costs abstract in a recent paper alfares 2007 inventory model with stock level dependent demand rate and variable holding cost international journal of production economics 108 1 2 259 265 presented an inventory model with a stock dependent demand rate and variable holding costs the analysis imposed a terminal condition that the inventory level at the end of the order cycle drop to zero and utilized a cost minimization objective however with a stock dependent demand rate this approach does not provide an optimal profit allowing ending inventory to be nonzero a profit maximization model and solution methodology are developed computational results indicate a substantial improvement in the solution realized by the proposed approach

the effect of sibling sex composition on women s education and earnings this paper documents the impact of siblings on the education of men and women born in the united states between 1920 and 1965 we examine the effect of the number and sex composition of a boy or girl s siblings on that child s educational attainment we find that throughout the century women s educational choices have been systematically affected by the sex composition of her siblings and that men s choices have not women raised only with brothers have received on average significantly more education than women raised with any sisters controlling for household size since sibling sex composition affects women s educational attainment and plausibly may be unrelated to other determinants of earnings it may provide a useful instrument for education in earnings functions for women our results suggest that standard estimates significantly underestimate the return to schooling for women

using stated preferences and beliefs to identify the impact of risk on poor households abstract whilst the importance of uncertainty in shaping economic behaviour of poor households is widely acknowledged empirically identifying the impact of risk is difficult by using data on risk preferences and perceptions of risk collected through hypothetical questions in combination with more traditional measures of a household s ability to deal with risk this article identifies the impact of risk on production decisions it shows both that data on stated preferences and beliefs can be usefully utilised to explain household behaviour and that risk has a significant impact on the production decisions of poor households

the interindustry structure of unionism earnings and earnings dispersion this study examines the relationship between unionism and earnings dispersion within u s manufacturing and nonmanufacturing industries the author hypothesizes not only that unionism narrows earnings dispersion as others have shown but also that the dispersion in earnings reflecting the degree of worker homogeneity influences the level of unionism estimation of a three equation model using 1970 three digit industry data provides evidence regarding the simultaneous determination of unionism earnings and earnings dispersion within u s industries the estimated equalizing effects of unionism on within industry earnings distributions are found to be significant both in the manufacturing and nonmanufacturing sectors the size of these estimates increasing after accounting for simultaneity in addition the dispersion in earnings does appear to affect the level of unionism although the evidence on this point is ambiguous

estimating the effects of unions on wage inequality in a panel data model with comparative advantage and nonrandom selection this article considers the estimation of the structure of wages in union and nonunion sectors it proposes an estimator that extends standard panel data techniques to the case in which the return to the permanent component of the error term is differently rewarded in the two sectors the econometric model is used to estimate the effect of unions on both the level and the variance of wages in canada the findings indicate that unions increase the average wage of workers and compress the returns to observable measures of skill and to a time invariant unobservable measure of skill

land inheritance and market transactions in uganda studies on the role of nonmarket land transactions remain limited this paper addresses two questions is land inheritance driven by underdeveloped land markets how does land inheritance influence land disposal and acquisition we use a switching regression model on household data from rural uganda we find that the initially landless or near landless households due to little or no land inheritance obtain land through land markets while those that are land rich dispose of land through land sales and bequests the results suggest that a process of land equalization is unfolding within the sample

allocation of land tenure rights in tigray how large is the gender bias this study investigates gender differences in land ownership and use in northern ethiopia female headed households have 23 smaller owned landholdings and 54 smaller operational landholdings household endowments of nonland productive inputs are important but decomposition analysis shows that differences in observable characteristics such as labor and oxen explain less than half of these differences whereas the remaining differences can be attributed to differences in returns to these characteristics the latter suggests a gender bias in land allocation the main policy recommendation is to strengthen women s opportunities to cultivate their land and continue the process of securing women s tenure rights

production inventory models for a damageable item with variable demands and inventory costs in an imperfect production process in this paper economic production quantity epq models for breakable or deteriorating item are developed with variable demands being dependent on time or on hand stock here rate of production and holding cost are time dependent unit production cost is a function of both production reliability indicator and production rate set up cost is also partially production rate dependent the production process produces some imperfect quantities which are instantly reworked at a cost to bring back those units to the perfect ones the production process ultimately depends on both time and reliability indicator the models are formulated as optimal control problems and the total profit functions with effect of inflation and time value of money are expressed as finite integrals over the finite planning horizon the problems are solved using euler lagrange function based on variational calculus and newton raphson method to determine the optimal production reliability indicator r and then corresponding production rates and total profits in some cases results of the models for deteriorating item are obtained as particular cases from those of breakable item models similarly results of simple epq models without damageability are deduced as particular cases numerical experiments are performed to illustrate the models both numerically and graphically

household bargaining power and agricultural supply response evidence from ethiopian coffee growers summary this paper investigates whether preference heterogeneity between spouses contributes to limited cash crop production in southern ethiopia using the value of livestock each spouse would take in the event of divorce as a measure of bargaining power this paper shows a significant negative correlation between the bargaining power proxies and coffee output livestock ownership during marriage does not have a significant impact on coffee production in contrast to the case in commercial production women s exit options have a weak positive effect on production of the staple crop enset

union wage practices and wage dispersion within establishments this study analyzes establishment level data primarily to examine the effect of unionism on the wage structure within establishments the major finding is that within establishment dispersion of wages is significantly narrower in unionized than in nonunionized establishments a pattern the author attributes in large part to unions wage practices such as single rate or automatic progression modes of wage payment as opposed to merit reviews and individual wage determination the data also show that dispersion in average wages is narrower among organized plants but by more modest amounts than the within establishment differential overall the evidence suggests a major role for explicit union wage policies in explaining the dispersion of wages within firms and in the economy as a whole

wage dispersion within firms and collective bargaining in spain abstract this paper analyses the determinants of bargained wage dispersion by professional groups within firms in spain estimations show that insider factors union density sales per employee and the average bargained wage level are the main determinants of wage dispersion

inventory models with the demand rate dependent on stock and shortage levels this paper investigates an inventory system in which the demand rate during stockout periods differs from that during the in stock period by a given amount the previous analysis conducted in this area formulated the model as a cost minimization model this type of formulation will intentionally try to decrease demand by increasing the stockout period in order to decrease costs this paper appropriately considers the model as a profit maximization model and develops a closed form solution the model is then further generalized to incorporate the effect of stock level dependent demand rates and considers initial stock dependent demand as well as instantaneous stock dependent demand rates

dowry and wife s welfare a theotrical and empirical analysis becker attributes the existence of marital transfers to inflexibility in the division of joint product within the marriage if that were the only reason we would not have observed the coexistence of dowries and bride prices this paper offers an alternative analysis while becker s interpretation is retained for bride prices a dowry is now represented as a premortem bequest by altruistic parents for a daughter it not only increases the wealth of the new conjugal household but also enhances the bargaining power of the bride in the allocation of the output within the household thereby safeguarding here welfare using micro data from taiwan we found that a dowry improves the bride s welfare whereas a bride price has no effect these empirical results support the theoretical predictions of the model

effect of intergenerational asset transfers on land distribution in rural cambodia case studies of three rice growing villages after land reallocation in the early 1980s inequality in landholdings has re emerged in rural cambodia besides land sales and purchases intergenerational transfers of assets may foster inequality in landholdings among second generation 2g couples who having wed after the 1980s reallocation received no land from the government data analysis of three rice growing villages reveals that land received directly from parents accounts for 18 41 of inequality in landholdings among sample 2g couples although net land gain after marriage primarily through purchases is the largest contributor to the inequality nonland assets received from parents positively affect the net gain direct and indirect effects combined assets received from parents account for 35 57 of inequality in landholdings the effect of assortative matching of the acreage received from parents has hitherto been small

an optimal procurement policy for items with an inventory level dependent demand rate and fixed lifetime abstract this paper investigates an optimal procurement policy for items with an inventory level dependent demand rate and fixed lifetime the demand rate is assumed to be a function of current inventory level and each unit has its fixed expiry date so any units which remain unused by their expiry date are considered outdated and must be disposed of for the system presented a mathematical model and solution methodology were developed sensitivity of the decision variables to changes in the parameter values is examined and future research needs are discussed in brief

land fragmentation and food insecurity in ethiopia this paper revisits the economic consequences of land fragmentation taking seriously concerns regarding the exogeneity of fragmentation its measurement and the importance of considering impacts in terms of welfare metrics using data that are well suited to addressing these issues the analysis finds that land fragmentation reduces food insecurity this result is robust to how fragmentation is measured and to how exogeneity concerns are addressed further the paper finds that land fragmentation mitigates the adverse effects of low rainfall on food security this is because households with diverse parcel characteristics can grow a greater variety of crop types

education and off farm work an investigation is presented of the determinants of educational selectivity in a framework that emphasizes the coordination of household members sectoral time allocation is based on members comparative advantage which in turn depends on the utilization and returns to schooling in the farm and nonfarm sectors central to the model is a knowledge spillover hypothesis that workers who participate in off farm work may still contribute knowledge to farm management estimation of the model is based on cross sectional chinese farm household data collected in 1990 from 204 households in sichuan province it is concluded that schooling does not enhance labour productivity when carrying out routine tasks that the contribution to farm efficiency by the most educated members is not affected by their non farm participation and that schooling increases labour market wage rates these empirical results give comparative advantage for the better educated farmers to work off the farm

the economics of polygyny in sub saharan africa female productivity and the demand for wives in cote d ivoire polygyny is still practiced throughout much of sub saharan africa with important social consequences this paper makes the first attempt to link african polygyny directly to the productivity of women in agriculture using micro data i develop a structural model of the demand for wives that disentangles wealth and substitution effects using a large household survey from cote d ivoire i find that marked geographic diversity in cropping patterns leads to regional variation in female labor productivity i also find that conditional on wealth men do have more wives when women are more productive that is cheaper this substitution effect may explain why polygyny declined in rural areas of cote d ivoire during agricultural development

long term impact of investments in early schooling empirical evidence from rural ethiopia abstract we examine the cumulative impact of early schooling investments on later schooling outcomes using enrollment status and relative grade attainment as short run and long run measures of schooling using a child level longitudinal data set from rural ethiopia we estimate a dynamic conditional schooling demand function where the coefficient estimate on the lagged dependent variable captures the impact of all previous period schooling inputs and resources we find that a child who is enrolled in the prior period is 33 percentage points more likely to be enrolled currently these lagged effects are stronger for girls and for children from higher income households

determining the optimal target for a process with multiple markets and variable holding costs abstract the determination of the quality target for a manufacturing process represents an intricate and fiscally vital decision this study examines methods for process target optimization in industries where several grades of consumer specifications and hence several quality grades of products may be sold within the same market in such situations manufacturers may hold goods that have been rejected by one customer to sell the same goods to another consumer in the same market at a later date the expected profit function for such firms must consider the holding costs as well as the profits associated with this sales strategy this study provides a conceptual and mathematical overview of such situations a method for identifying the optimal process target that reflects holding costs is presented and illustrated in the context of the steel galvanization industry