The Earned Income Tax Credit and the Labor Supply of Married Couples

Over 18 million taxpayers are projected to receive the Earned Income Tax Credit (EITC) in tax year 1997, at a total cost to the federal government of about 25 billion dollars. The EITC is refundable, so any amount of the credit exceeding the family’s tax liability is returned in the form of a cash refund. Advocates of the credit argue that this redistribution occurs with much less distortion to labor supply than that caused by other elements of the welfare system. This popular view that the credit “encourages work effort” is unlikely to hold among married couples. Theory suggests that primary earners (typically men) would increase labor force participation, but secondary earners would reduce their labor supply in response to an EITC. We study the labor supply response of married couples to several EITC expansions between 1984 and 1996. Although our primary interest is the response to changes in the budget set induced by the EITC, our estimation strategy takes account of budget set changes caused by federal tax policy, and by cross-sectional variation in wages, income, and family size. We use both quasi-experimental and reduced-form labor supply models to estimate the impact of EITC-induced tax changes. The results suggest that EITC expansions between 1984 and 1996 increased married men’s labor force participation only slightly but reduced married women’s labor force participation by over a full percentage point. Overall, the evidence suggests that family labor supply and pre-tax family earnings fell among married couples. Our results imply that the EITC is effectively subsidizing married mothers to stay at home, and therefore have implications for the design of the program.

Data-Driven Analysis Of Progressive Design Build In Water And Wastewater Infrastructure Projects

The United States has invested heavily in water and wastewater infrastructure projects to address growing demand and aging systems. To ensure the effective delivery of these projects, agencies are shifting toward alternative delivery methods such as progressive design build (PDB), which has demonstrated accelerated schedule and enhanced cost performance across the literature as well as multiple projects compared to traditional DB. This has raised a need for evaluating PDB\u27s state of adoption and performance in the water and wastewater sector. To this end, the authors: (1) conducted descriptive and statistical analyses of the 21 PDB water and wastewater projects available on the Design-Build Institute of America database evaluating their characteristics and performance metrics; (2) investigated the frequency of materialized risks impacting schedule and cost in these projects; and finally (3) identified the key adoption drivers and challenges for PDB in the water and wastewater sector by triangulating findings from the studied narratives with a literature and practice review. Results revealed that 71% and 57% of the investigated projects were completed on or before the contracted schedules and costs, respectively. From the studied project narratives, owner-led changes and COVID-19 impacts were the most frequently encountered risks. Also, it was shown that project planning and risk management drivers were the most influential causes for PDB adoption, whereas legal and contractual restrictions as well as the owner\u27s mindset and culture-related concerns were the most pressing challenges. This study contributes to the body of knowledge by delivering managerial insights through an aggregated snapshot of PDB implementation in the water and wastewater sector. Ultimately, the provided managerial insights can assist stakeholders in making better-informed decisions by weighing the advantages and challenges of PDB identified in this research against more traditional delivery approaches

Development of chitosan-glucose and chitosan-citric complexes edible coating to improve tomatoes post-harvest quality

 The effect of different shrimp chitosan molecular weights as well as shrimp chitosan complexes (chitosan-glucose and chitosan-citric) on the quality characteristics of the stored (at 7°C±2°C and 90% RH) tomato fruits (Lycopersicum esculentum) was investigated.  Coating tomatoes with high molecular weight chitosan (H.M.C.G) significantly improved firmness and weight loss.  The lowest weight loss was found in high molecular weight chitosan-glucose (H.M.C.G) treatment followed by the fruits coated with high molecular weight chitosan (HMC) and then uncoated tomato fruits.  Both molecular weights was clear on retarding the total acidity loss especially for stored tomato fruit coated with low molecular weight chitosan, while control tomatoes exhibited a larger reduction (p ≤ 0.05) in total acidity over storage.  Meanwhile, the increasing of cold storage time significantly (p ≥ 0.05) increased the pH in all uncoated and coated tomatoes.  Generally, no significant (P > 0.05) difference was observed in pH, titratable acidity and total soluble solids (T.S.S.) as well as sensory attributes among the tomato fruits coated with chitosan, chitosan citric and chitosan glucose.  Meanwhile, the fruits coated with low molecular weight chitosan had a higher (p ≥ 0.05) T.S.S. compared with that coated by the high molecular weight chitosan.   Keywords: chitosan, edible coating, tomatoes, firmness and weight loss

The frequency of IgM-anti HAV in the sera of patients with hepatitis in Iraq

Three hundred and fifty five patients with hepatitis were investigated in this study all cases gave negative result with HBs Ag , IgM-anti HCV , IgM-anti HEV, IgM-anti HDV and anti-HIV tests . The frequency of IgM-anti HAV was 113 and the percentage was 32 % in all ages but when these patients divided into five groups dependent on ages. The highest percentage of IgM-anti HAV was (45%) in age 41 year

Genetic Algorithm Optimization Model for Determining the Probability of Failure on Demand of the Safety Instrumented System

A more accurate determination for the Probability of Failure on Demand (PFD) of the Safety Instrumented System (SIS) contributes to more SIS realiability, thereby ensuring more safety and lower cost. IEC 61508 and ISA TR.84.02 provide the PFD detemination formulas. However, these formulas suffer from an uncertaity issue due to the inclusion of uncertainty sources, which, including high redundant systems architectures, cannot be assessed, have perfect proof test assumption, and are neglegted in partial stroke testing (PST) of impact on the system PFD. On the other hand, determining the values of PFD variables to achieve the target risk reduction involves daunting efforts and consumes time. This paper proposes a new approach for system PFD determination and PFD variables optimization that contributes to reduce the uncertainty problem. A higher redundant system can be assessed by generalizing the PFD formula into KooN architecture without neglecting the diagnostic coverage factor (DC) and common cause failures (CCF). In order to simulate the proof test effectiveness, the Proof Test Coverage (PTC) factor has been incorporated into the formula. Additionally, the system PFD value has been improved by incorporating PST for the final control element into the formula. The new developed formula is modelled using the Genetic Algorithm (GA) artificial technique. The GA model saves time and effort to examine system PFD and estimate near optimal values for PFD variables. The proposed model has been applicated on SIS design for crude oil test separator using MATLAB. The comparison between the proposed model and PFD formulas provided by IEC 61508 and ISA TR.84.02 showed that the proposed GA model can assess any system structure and simulate industrial reality. Furthermore, the cost and associated implementation testing activities are reduced

Transmitters and receivers in SiGe BiCMOS technology for sensitive gas spectroscopy at 222 - 270 GHz

This paper presents transmitter and receiver components for a gas spectroscopy system. The components are fabricated in IHP's 0.13 μm SiGe BiCMOS technology. Two fractional-N phase-locked loops are used to generate dedicated frequency ramps for the transmitter and receiver and frequency shift keying for the transmitter. The signal-to-noise ratio (SNR) for the absorption line of gaseous methanol (CH 3 OH) at 247.6 GHz is used as measure for the performance of the system. The implemented mixer-first receiver allows a high performance of the system due to its linearity up to an input power of -10 dBm. Using a transmitter-array with an output power of 7 dBm an SNR of 4660 (integration time of 2 ms for each data point) was obtained for the 247.6 GHz absorption line of CH 3 OH at 5 Pa. We have extended our single frequency-band system for 228 - 252 GHz to a 2-band system to cover the range 222 - 270 GHz by combining corresponding two transmitters and receivers with the frequency bands 222 - 256 GHz and 250 - 270 GHz on single transmitter- and receiver-chips. This 2-band operation allows a parallel spectra acquisition and therefore a high flexibility of data acquisition for the two frequency-bands. The 50 GHz bandwidth allows for highly specific and selective gas sensing. © 2019 Author(s)