巴黎第十大学

The aim of change-point detection is to identify behavioral shifts within time series data. This article focuses on scenarios where the data are derived from a heterogeneous Poisson process or a marked Poisson process. We present a methodology for detecting multiple offline change-points using a minimum contrast estimator. Specifically, we address how to manage the continuous nature of the process given the available discrete observations. Additionally, we select the appropriate number of changes via a cross-validation procedure, which is particularly effective given the characteristics of the Poisson process. Lastly, we show how to use this methodology for self-exciting processes with changes in the intensity. Through experiments, with both simulated and real datasets, we showcase the advantages of the proposed method, which has been implemented in the R package.

The index of a matrix is a fundamental invariant in the analysis of singular matrices and their generalized inverses. While sharp results are available for block triangular matrices, the corresponding theory for anti-triangular block matrices is less developed. In this paper, we study matrices of the form M= [ A B] , C 0 under algebraic constraints on the blocks. Building on additive decompositions involving von Neumann inverses, we relate the index of M to invariance properties of the index and minimal polynomial of expressions of the form A2A-+ I-AA-, where A-is any von Neumann inverse of A. This connection provides an effective mechanism to control the index of M through suitable factorizations and associated block products. As a consequence, we derive explicit lower and upper bounds for the index of M in terms of the index of A and of BC, and characterize situations in which these bounds are attained. Under additional annihilation or orthogonality conditions on the blocks, we obtain closed-form representations for the Drazin inverse of M. Applications to adjacency matrices of directed graphs illustrate the sharpness of the bounds and the applicability of the results to structured matrices arising in graph-theoretic settings.

OBJECTIVE:Previous research suggests that children with Attention-Deficit/Hyperactivity Disorder (ADHD) have difficulties processing gaze cues, potentially impairing their social interactions. This study evaluated the psychometric properties of TooN, a test designed to assess the ability to follow nonverbal social cues. We examined its clinical validity by comparing performance in children with ADHD and typically developing peers, as well as its internal consistency and test-retest reliability. METHOD:Clinical validity and internal consistency were assessed in 25 children with ADHD (mean age = 105 months, SD = 17; 6 girls) and 100 typically developing children matched for age and sex. Test-retest reliability was examined in an independent sample of 28 typically developing children (mean age = 103 months, SD = 17; 17 girls) who completed the task twice over a three-week interval. RESULTS:Children with ADHD showed longer reaction times and made more errors than typically developing peers. While cueing effects did not significantly differ between groups, only typically developing children showed a reliable gaze cueing effect, and both groups responded to pointing cues. Reaction time measures showed excellent internal consistency in both groups and moderate-to-good test-retest reliability in typically developing children, while cueing effects showed lower reliability. Accuracy measures were highly reliable in the ADHD group but less so in controls, possibly due to ceiling effects. CONCLUSIONS:TooN provides preliminary evidence relevant to assessing nonverbal social cue-following in children with and without ADHD. The absence of a reliable gaze cueing effect in ADHD is consistent with gaze-processing difficulties and supports the task's relevance for further investigation. However, the limited reliability of cueing effect scores and the absence of test-retest reliability data in ADHD indicate that findings should be interpreted cautiously. Further research should establish test-retest reliability and convergent validity in clinical samples before broader clinical applicability can be determined.

A method for generating dual high-order orbital angular momentum (OAM) modes by integrating spoof surface plasmon polariton (SSPPs) and spoof localized surface plasmon (SLSPs) is proposed. The proposed design consists of N rotationally arranged SSPP waveguides periodically loaded with SLSP patches, which enables broadband circularly polarized (CP) radiation and introduces a dynamic phase. Unlike conventional approaches that rely on excitation phase control and complex feeding networks, the proposed method utilizes dynamic and geometric phases to synthesize the required phase distribution for high-order OAM modes, thereby eliminating the need for phase-shifting networks. Moreover, exploiting the leaky-wave theory, dual high-order OAM modes with l = -N + 1 and l = N + 1 are generated by varying the frequency to alter the dynamic phase. The experimental results confirm that the proposed device is capable of generating high-order l = -7 and l = +9 OAM modes at 9.7 and 13.0 GHz, with gains (divergence angles) of 8.4 dBic (33 degrees) and 5.6 dBic (23 degrees), respectively. This work provides a phase-network-free solution for dual high-order OAM generation with frequency-controlled mode switching, demonstrating potential for applications in sensing, radar detection, and mode-division multiplexing systems for wireless communications.

This paper evaluates the impact of new universities established under France's U2000 Plan on local human capital in secondary cities. Using the synthetic control method, it finds these universities increased the share of higher educated residents (excluding students) by 4 percentage points over 27 years (an 18% rise from the counterfactual). This effect implies broader attraction mechanisms, not merely students staying in the area, and does not displace graduates near historical universities. The increase in local human capital varies across cases and is associated with employment growth, an influx of young residents and a rise in skilled employment.