when shareholders have agreement about divestiture of company’s share in stock exchange, they decide to change and improve their business ownership structure and the presence of a large shareholder to help divestiture. the present study was aimed to investigate the effect of presence of large shareholder to tends firm to divestiture by a new approach. for this purpose, the propensity score a sa...

By comparing 401(k) eligible and ineligible households’ wealth, this paper estimates that, on average, about one half of 401(k) balances represent new private savings, and about one quarter of 401(k) balances represent new national savings. Responses to eligibility vary considerably, however, with households who normally save the most largely contributing funds they would have saved anyway. Thi...

aim: this study aimed to assess the relationship of screen time and metabolic syndrome (mets) among iranian adolescents. materials and methods  in this nationwide study, the propensity score (ps) was used in a matched case-control study design. the data was obtained from 5,625 students aged 10-18 years, who participated in a national school-based surveillance program. mets was defined according...

background: several studies have demonstrated an increased risk of congenital hypothyroidism (ch) in girls in comparison to boys. objectives: the aim of this study was to determine the potential interactions that are able to change the effect of gender on congenital hypothyroidism. patients and methods: we conducted a matched 1:4 case-control study in hamadan province, western of iran, from 200...

In observational studies, investigators usually do not have the same control over the treatment assignment as they do with randomized controlled studies. As a result, the treatment and control groups may have a large difference on their observed covariates. These differences could lead to bias in estimating treatment effects. There are several propensity score based methods that could reduce th...

We are interested in estimating the average effect of a binary treatment on a scalar outcome. If assignment to the treatment is exogenous or unconfounded, that is, independent of the potential outcomes given covariates, biases associated with simple treatment-control average comparisons can be removed by adjusting for differences in the covariates. Rosenbaum and Rubin (1983) show that adjusting...

The Effect of Breastfeeding on Children’s Cognitive and Noncognitive Development This paper uses propensity score matching methods to investigate the relationship between breastfeeding and children’s cognitive and noncognitive development. We find that breastfeeding for four weeks is positively and statistically significantly associated with higher cognitive test scores, by around one tenth of ...

The aim is to assess the effect of imprisonment on rape myth acceptance. The research used a sample of male prisoners incarcerated for non-sexual crimes (n = 98) and a sample of males drawn from the general population (n = 160). Simple linear regression did not indicate a significant effect of incarceration on rape myth acceptance. After controlling for background covariates using propensity sc...

Observational studies draw inferences about the possible effect of a treatment on subjects, where the assignment of subjects into a treated group versus a control group is outside the control of the investigator. Let r1(x) be the response when a unit with covariates x receives the treatment (z = 1), and r0(x) be the response when that unit does not receive the treatment (z = 0). Then one is int...

We are interested in estimating the average effect of a binary treatment on a scalar outcome. If assignment o the treatment is exogenous or unconfounded, that is, independent of the potential outcomes given covariates, biases associated with simple treatmentcontrol average comparisons can be removed by adjusting for differences in the covariates. Rosenbaum and Rubin (1983) show that adjusting s...