Likelihood-based tests in zero-inflated power series models

We address the issue of performing testing inference in the class of zero-inflated power series models. These models provide a straightforward way of modelling count data and have been widely used in practical situations. The likelihood ratio, Wald and score statistics provide the basis for testing the parameter of inflation of zeros in this class of models. In this paper, in addition to the well-known test statistics, we also consider the recently proposed gradient statistic. We conduct Monte Carlo simulation experiments to evaluate the finite-sample performance of these tests for testing the parameter of inflation of zeros. The numerical results show that the new gradient test we propose is more reliable in finite samples than the usual likelihood ratio, Wald and score tests. An empirical application to real data is considered for illustrative purposes.     

Assessing noninferiority: Evaluating efficacy of a new treatment without complete data

The FDA released the final guidance on noninferiority trials in November 2016. In noninferiority trials, validity of the assessment of the efficacy of the test treatment depends on the control treatment's efficacy. Therefore, it is critically important that there be a reliable estimate of the control treatment effect—which is generally obtained from historical trials, and often assumed to hold in the current setting (the assay constancy assumption). Validating the constancy assumption requires clinical data, which are typically lacking. The guidance acknowledges that “lack of constancy can occur for many reasons.” We clarify the objectives of noninferiority trials. We conclude that correction for bias, rather than assay constancy, is critical to conducting valid noninferiority trials. We propose that assay constancy not be assumed and discounting or thresholds be used to address concern about loss of historical efficacy. Examples are provided for illustration.     

TIMING IS MONEY: DOES LUMP‐SUM PAYMENT OF THE EARNED INCOME TAX CREDIT AFFECT SAVINGS AND DEBT?

Earned income tax credit (EITC) benefit income is paid out in a lump‐sum around tax time. We investigate whether savings and debt among EITC‐eligible families reflect the timing of payments. Using nationally representative, individual‐level data on self‐reported debt and savings outcomes, we search for differences in monthly behavior between EITC‐eligible and ‐ineligible households. We find evidence that credit card and unsecured debt holding among EITC‐eligible families reflects the timing of the EITC, with low debt levels at tax time relative to other months. Debt holding among ineligible families with children does not exhibit a similar pattern. We find limited evidence of intrayear patterns in savings behavior among EITC‐eligible families. (JEL D14, I38, H23)     

“I was Excited by the Idea of a Project that Focuses on those Unasked Questions” Co‐Producing Disability Research with Disabled Young People

In this article, we detail the politics and practicalities of co‐produced disability research with disabled young people with life‐limiting and life‐threatening impairments. We centre an ESRC‐funded arts‐informed co‐produced research project that has brought together a Co‐Researcher Collective of disabled young people. Co‐production is an established approach; however, our co‐researchers have led us to develop inclusive research practices that engage with online social research methods in innovative ways. As we detail our experiences, we aim to encourage disability studies researchers and others to adopt virtual environments when researching with and for the lives of disabled people.     

The Relational Production of Workplace Equality: The Case of Worker-Recuperated Businesses in Argentina

Work organizations are commonly studied as sites that produce and reproduce inequality. But we know much less about how organizations promote equality. This article examines efforts to broaden access to power, opportunity, and resources in Hotel Bauen, a worker-recuperated business that was converted from a privately-owned company into a worker-run cooperative. Drawing on extensive ethnographic and archival research, I analyze efforts to redesign and redefine work through collective decision-making, job rotation, and pay equity. The article concludes by identifying three mechanisms of equality—inclusion, opportunity distribution, and symbolic leveling—to theorize the relational production of workplace equality and complement the near-exclusive focus on inequality and its effects.

     

Can urban greening increase vector abundance in cities? The impact of mowing,local vegetation,and landscape composition on adult mosquito populations

Worldwide, cities are investing in greenspace to enhance urban quality of life and conserve biodiversity. Cities should ensure these investments do not unintentionally result in ecosystem disservices. Municipal management decisions regarding urban greenspaces, such as mowing frequency, could influence mosquito communities and public health. We examined how mowing, resultant vegetation characteristics, and landscape context influenced adult mosquito abundance in urban vacant lots. We sampled adult Culex and Aedes mosquitoes in a network of vacant lots within eight Cleveland, Ohio, USA neighborhoods in 2015 and 2016 using CO₂-baited light traps and grass-infused gravid traps. For each lot, we quantified vegetation characteristics, including plant diversity, bloom area, and biomass, as well as the surrounding landscape composition at radii of 60 and 1000 m. We found that periodic mowing did not significantly affect mosquito abundances. However, vacant lots with more diverse plant communities were associated with a greater light trap capture of both Culex and Aedes. Both mosquito genera declined in light trap catches with increased impervious surface at 60 m. Similarly, Culex (gravid trap) declined with the amount of built infrastructure at 1000 m. In contrast, Aedes (light trap) increased with the concentration of buildings in the landscape at 1000 m. Our findings indicate that reducing the frequency of mowing within vacant lots will not necessarily increase adult mosquito abundance. Nonetheless, mosquito surveillance and management should be considered when planning conservation-focused greenspaces, as vegetation design choices and the landscape context of a site do influence vector abundance and potentially disease risk.

     

Opening the government’s black boxes: freedom of information and algorithmic accountability

Freedom of information laws are intended to illuminate how governments operate. However, the operations of governments increasingly involve algorithms, such as those used to recommend criminal sentencing and determine eligibility for social services. Algorithms function as ‘black boxes’ that turn inputs into outputs using processes that are often, by design, not transparent. Freedom of information laws allow one potential means for algorithmic transparency. However, whether such laws can be used to access algorithms is unclear. This research examines, in two ways, the availability of government algorithms to the public. First, this study examines laws, regulations, advisory opinions, and court rulings relevant to the disclosure of algorithms. The second part of this study analyzes actual responses by US government agencies to Freedom of Information Act requests for algorithms. This study concludes that governmental policies and practices related to algorithmic disclosure are inconsistent. Such inconsistencies suggest a need for better mechanisms to hold government algorithms accountable.     

The EITC and the labor supply of adult dependents: direct effects and family income effects

Tax data suggest that the population of adult dependents—adults relying on the support of others for the majority of their financial needs—has more than doubled over the last decade. However, little is known about how taxes affect the labor supply decisions of this population. This paper provides an initial investigation, studying the impact of the Earned Income Tax Credit (EITC) expansions of the early 1990s on the labor supply of adult dependents living with their relatives. I find that dependent individuals who were not a part of the nuclear family responded to the EITC expansions, increasing labor force participation by about 5 percentage points. For adult children, I show that the absence of a net response is likely due to an unexpected consequence of the EITC: expanded family credits led to a decrease in their labor force participation.     

Correction to: Parental Status and Biological Functioning: Findings from the Nashville Stress and Health Study

Population Research and Policy Review - Unfortunately, due to an error upon submission of this article, the article was published with an incomplete author group. Dr. Katherine L. Friedman was not...