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This study aims to investigate dynamic relations among office property price indices of 10 major cities in China for the years 2005–2021.

Using monthly data, the authors adopt vector error correction modeling and the directed acyclic graph for the characterization of contemporaneous causality among the 10 indices.

The PC algorithm identifies the causal pattern, and the linear non-Gaussian acyclic model algorithm further determines the causal path from which we perform innovation accounting analysis. Sophisticated price dynamics are found in price adjustment processes following price shocks, which are generally dominated by the top tier of cities.

This suggests that policies on office property prices, in the long run, might need to be planned with particular attention paid to the top tier of cities.

This study aims to describe and analyze the factors associated with dependence and motivation to stop smoking in patients with schizophrenia.

This descriptive, analytical study was conducted between October 2021 and April 2023 at two psychiatric centers in Morocco. The study population consisted of 274 smokers diagnosed with schizophrenia, who were examined just before their discharge. In addition to sociodemographic and economic data, tobacco use status and clinical information, the authors assessed dependence with Fagerström Test for Nicotine Dependence (FTND), motivation to quit and depression.

Around three-quarters (74%) smoked more than 10 cigarettes a day, with a mean FTND score of 5.61 (±1.94). Dependence was reported in 76% of smokers. More than two-thirds (69%) had made at least one attempt to quit, and almost all participants (99%) had done so without medical assistance. Nicotine dependence was associated with income, illness duration, motivation to stop smoking and depression. In addition, lower income, level of education, number of hospitalizations, attempts to stop smoking and nicotine dependence were associated with motivation to quit tobacco use. However, depression was not associated with motivation to stop smoking.

The present study has the following limitations: the cross-sectional nature of the study does not allow for temporal evaluation, the sampling technique does not allow for generalization of the results, participants’ responses may be subjective despite the use of validated psychometric scales.

The results of this research have important public health implications: Duration of schizophrenia progression was associated with nicotine dependence – highlighting the need to offer help as soon as possible after diagnosis, as a preventative measure; Calgary depression score was a factor associated with increased dependence – suggesting that screening and additional help for people with co-existing mental health problems could be important. Similarly, the onset of depression after the development of schizophrenia should be monitored.

The authors have further searched the literature and have not found similar studies. The absence of such studies justifies the significance of this research, and its results will be valuable for publication to guide researchers in the treatment of tobacco dependence and, furthermore, to guide the preventive efforts of health authorities in Morocco. Additionally, to the best of the authors’ knowledge, this study is the first of its kind in Morocco and among the few in North Africa.

Visual feedback control is a promising solution for robots work in unstructured environments, and this is accomplished by estimation of the time derivative relationship between the image features and the robot moving. While some of the drawbacks associated with most visual servoing (VS) approaches include the vision–motor mapping computation and the robots’ dynamic performance, the problem of designing optimal and more effective VS systems still remains challenging. Thus, the purpose of this paper is to propose and evaluate the VS method for robots in an unstructured environment.

This paper presents a new model-free VS control of a robotic manipulator, for which an adaptive estimator aid by network learning is proposed using online estimation of the vision–motor mapping relationship in an environment without the knowledge of statistical noise. Based on the adaptive estimator, a model-free VS schema was constructed by introducing an active disturbance rejection control (ADRC). In our schema, the VS system was designed independently of the robot kinematic model.

The various simulations and experiments were conducted to verify the proposed approach by using an eye-in-hand robot manipulator without calibration and vision depth information, which can improve the autonomous maneuverability of the robot and also allow the robot to adapt its motion according to the image feature changes in real time. In the current method, the image feature trajectory was stable in the camera field range, and the robot’s end motion trajectory did not exhibit shock retreat. The results showed that the steady-state errors of image features was within 19.74 pixels, the robot positioning was stable within 1.53 mm and 0.0373 rad and the convergence rate of the control system was less than 7.21 s in real grasping tasks.

Compared with traditional Kalman filtering for image-based VS and position-based VS methods, this paper adopts the model-free VS method based on the adaptive mapping estimator combination with the ADRC controller, which is effective for improving the dynamic performance of robot systems. The proposed model-free VS schema is suitable for robots’ grasping manipulation in unstructured environments.

The purpose of this study is to evaluate whether the classification of the equity mutual fund depends on the performance measure used.

The sample for this study includes stock mutual funds for the USA, Europe and emerging market economies covering the period 2010 to 2020. Using more than 20 performance measures the results are compared using the Sharpe ratio as the reference.

The results show that performance measures based on absolute reward–risk ratios like Sortino, Treynor, etc. have similar rankings, because in general the numerator (mean excess return) is the same. However, when the authors employ other types of performance measures, results may be significantly different, especially in the case of metrics for “incremental returns”, i.e. alphas. Focussing on markets, their results show that choosing performance measures is more relevant for emerging markets.

The sample is only limited to the USA, Europe and the emerging market, and there are other performance metrics in the literature which have not been covered in this work.

The ordering of equity mutual funds depends on the measure used, specially if investors employ factor models to measure excess returns (alphas). Hence, policy formulation on disclosure of mutual fund performance should encourage the use of several metrics from different families. Investors must be aware of the different rankings made and the most appropriate metrics based on their preferences.

This paper focusses specifically on the effect that performance metrics have on relative fund performance. Previous studies have ignored alpha metrics to rank funds, which are commonly employed by investors. The authors’ study performs an analysis for three different markets considering the two main developed ones (the American and European equity markets), as well as the emerging one, largely ignored until now.