Sliders,visual analogue scales,or buttons: Influence of formats and scales in mobile and desktop surveys

ABSTRACT

In an experiment dealing with the use of personal computer, tablet, or mobile, scale points (up to 5, 7, or 11) and response formats (bars or buttons) are varied to examine differences in mean scores and nonresponse. The total number of “not applicable” answers does not vary significantly. Personal computer has the lowest item nonresponse, followed by mobile and tablet, and a lower mean score than for mobile. Slider bars showed lower mean scores and more nonresponses than buttons, indicating that they are more prone to bias and difficult in use. Sider bars, which work with a drag-and-drop principle, perform worse than visual analogue scales working with a point-and-click principle and buttons. Five-point scales have more nonresponses than eleven-point scales. Respondents evaluate 11-point scales more positively than shorter scales.     

Defective models induced by gamma frailty term for survival data with cured fraction

In this paper, we propose a defective model induced by a frailty term for modeling the proportion of cured. Unlike most of the cure rate models, defective models have advantage of modeling the cure rate without adding any extra parameter in model. The introduction of an unobserved heterogeneity among individuals has bring advantages for the estimated model. The influence of unobserved covariates is incorporated using a proportional hazard model. The frailty term assumed to follow a gamma distribution is introduced on the hazard rate to control the unobservable heterogeneity of the patients. We assume that the baseline distribution follows a Gompertz and inverse Gaussian defective distributions. Thus we propose and discuss two defective distributions: the defective gamma-Gompertz and gamma-inverse Gaussian regression models. Simulation studies are performed to verify the asymptotic properties of the maximum likelihood estimator. Lastly, in order to illustrate the proposed model, we present three applications in real data sets, in which one of them we are using for the first time, related to a study about breast cancer in the A.C.Camargo Cancer Center, São Paulo, Brazil.     

Respect in intergenerational relationships: Young adult women’s motivations

Care and respect are two sides of the same coin, yet very little is known about respect shown by younger women in relation to people aged 60 and older. This study sets out to explore what motivates young adult women to respect older people. Twenty-five post-graduate women from a tertiary education institution in South Africa participated in the Mmogo-method®, a projective visual data-collection method, to produce textual and visual data. These were analysed using sequential and visual analysis. Findings reported combinations of motivational types for respect of older people, on a continuum from extrinsic (socialised normative values) to intrinsic (personal choice and empathy), and from conditional to unconditional, namely: extrinsic/conditional; extrinsic/unconditional; self-motivated/conditional and self-motivated/unconditional. Respect as an impact on relational interactions between people is either constructive and encouraging or damaging and disparaging. Interpersonal risks are associated with motivation and this could affect future interactions and manifestations of intergenerational respect.     

The concept of a child within sub‐Saharan African migrant homes: Reconciling culture and child rights

As international migration increases, the Australian socio‐cultural and political context in which sub‐Saharan African migrant families are settling is causing tension between traditional sub‐Saharan African migrant definitions of child and childhood experiences and host nation definitions particularly when compared with the child protection system. This paper seeks to explore and highlight the fundamental values and differences that determine perceptions and treatment of children within traditional sub‐Saharan African communities. Using a qualitative design, this study was influenced by acculturation theory. Four major themes emerged from the analysis: (a) culture and the sub‐Saharan African child, (b) moulding good children, (c) family functioning and relationships, and (d) host context: perceptions of Australian mainstream parenting. The study found that in order to successfully make decisions that are in the best interest of sub‐Saharan African migrant children that come to the attention of the child protection system, discussions about children rights can only yield good outcomes when the child's socio‐cultural environment is considered.     

Some nonparametric methods for changepoint problems

A general model for changepoint problems is discussed from a nonparametric viewpoint. The test statistics introduced are based on Cramér-von Mises functionals of certain processes and are shown to converge in distribution to corresponding Gaussian functionals (under the assumption of no change in distribution, H₀). We also demonstrate how the distribution of the limiting Gaussian functionals may be tabulated. Finally, properties of the tests under the alternative hypothesis of exactly one changepoint occurring are studied, and some examples are given.     

An Automated MCEM Algorithm for Hierarchical Models with Multivariate and Multitype Response Variables

In this article, we consider a model allowing the analysis of multivariate data, which can contain data attributes of different types (e.g., continuous, discrete, binary). This model is a two-level hierarchical model which supports a wide range of correlation structures and can accommodate overdispersed data. Maximum likelihood estimation of the model parameters is achieved with an automated Monte Carlo expectation maximization algorithm. Our method is tested in a simulation study in the bivariate case and applied to a data set dealing with beehive activity.     

On an improved Erdő-Rényi-type law for increments of partial sums

Let X₁, X₂,… be an independently and identically distributed sequence with ξX₁ = 0, ξ exp (tX₁ < ∞ (t ≧ 0) and partial sums S_n = X₁ + … + X_n. Consider the maximum increment D₁ (N, K) = max_{0≤n ≤ N - K} (S_{n + K} - S_n)of the sequence (S_n) in (0, N) over a time K = K_N, 1 ≦ K ≦ N. Under appropriate conditions on (K_N) it is shown that in the case K_N/log N → 0, but K_N/(log N)^1/2 → ∞, there exists a sequence (α_N) such that K_-1/2 D₁ (N, K) - α_N converges to 0 w. p. 1. This result provides a small increment analogue to the improved Erd?s-Rényi-type laws stated by Csörg? and Steinebach (1981).