Customer attrition analysis for financial services using proportional hazard models

2004 ◽  
Vol 157 (1) ◽  
pp. 196-217 ◽  
Author(s):  
Dirk Van den Poel ◽  
Bart Larivière
2021 ◽  
Vol 20 ◽  
pp. 153303382110049
Author(s):  
Tao Ran ◽  
ZhiJi Chen ◽  
LiWen Zhao ◽  
Wei Ran ◽  
JinYu Fan ◽  
...  

Background and Objective: Gastric cancer (GC) is a common tumor malignancy with high incidence and poor prognosis. Laminin is an indispensable component of basement membrane and extracellular matrix, which is responsible for bridging the internal and external environment of cells and transmitting signals. This study mainly explored the association of the LAMB1 expression with clinicopathological characteristics and prognosis in gastric cancer. Methods: The expression data and clinical information of gastric cancer patients were downloaded from The Cancer Genome Atlas (TCGA) and Asian Cancer Research Group (ACRG). And we analyzed the relationship between LAMB1 expression and clinical characteristics through R. CIBERSORTx was used to calculate the absolute score of immune cells in gastric tumor tissues. Then COX proportional hazard models and Kaplan-Meier curves were performed to evaluate the role of LAMB1 and its influence on prognosis in gastric cancer patients. Finally, GO and KEGG analysis were applied for LAMB1-related genes in gastric cancer, and PPI network was constructed in Cytoscape software. Results: In the TCGA cohort, patients with gastric cancer frequently generated LAMB1 gene copy number variation, but had little effect on mRNA expression. Both in the TCGA and ACRG cohorts, the mRNA expression of LAMB1 in gastric cancer tissues was higher than it in normal tissues. All patients were divided into high expression group and low expression group according to the median expression level of LAMB1. The elevated expression group obviously had more advanced cases and higher infiltration levels of M2 macrophages. COX proportional hazard models and Kaplan-Meier curves revealed that patients with enhanced expression of LAMB1 have a worse prognosis. GO/KEGG analysis showed that LAMB1-related genes were enriched in PI3K-Akt signaling pathway, focal adhesion, ECM-receptor interaction, etc. Conclusions: The high expression of LAMB1 in gastric cancer is related to the poor prognosis of patients, and it may be related to microenvironmental changes in tumors.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Hirokazu Honda ◽  
Miho Kimachi ◽  
Noriaki Kurita ◽  
Nobuhiko Joki ◽  
Masaomi Nangaku

Abstract Recent studies have reported that high mean corpuscular volume (MCV) might be associated with mortality in patients with advanced chronic kidney disease (CKD). However, the question of whether a high MCV confers a risk for mortality in Japanese patients remains unclear. We conducted a longitudinal analysis of a cohort of 8571 patients using data derived from the Japan Dialysis Outcomes and Practice Patterns Study (J-DOPPS) phases 1 to 5. Associations of all-cause mortality, vascular events, and hospitalization due to infection with baseline MCV were examined via Cox proportional hazard models. Non-linear relationships between MCV and these outcomes were examined using restricted cubic spline analyses. Associations between time-varying MCV and these outcomes were also examined as sensitivity analyses. Cox proportional hazard models showed a significant association of low MCV (< 90 fL), but not for high MCV (102 < fL), with a higher incidence of all-cause mortality and hospitalization due to infection compared with 94 ≤ MCV < 98 fL (reference). Cubic spline analysis indicated a graphically U-shaped association between baseline MCV and all-cause mortality (p for non-linearity p < 0.001). In conclusion, a low rather than high MCV might be associated with increased risk for all-cause mortality and hospitalization due to infection among Japanese patients on hemodialysis.


Author(s):  
Peyman Mazidi ◽  
Mian Du ◽  
Lina Bertling Tjernberg ◽  
Miguel A Sanz Bobi

In this article, a parametric model for health condition monitoring of wind turbines is developed. The study is based on the assumption that a wind turbine’s health condition can be modeled through three features: rotor speed, gearbox temperature and generator winding temperature. At first, three neural network models are created to simulate normal behavior of each feature. Deviation signals are then defined and calculated as accumulated time-series of differences between neural network predictions and actual measurements. These cumulative signals carry health condition–related information. Next, through nonlinear regression technique, the signals are used to produce individual models for considered features, which mathematically have the form of proportional hazard models. Finally, they are combined to construct an overall parametric health condition model which partially represents health condition of the wind turbine. In addition, a dynamic threshold for the model is developed to facilitate and add more insight in performance monitoring aspect. The health condition monitoring of wind turbine model has capability of evaluating real-time and overall health condition of a wind turbine which can also be used with regard to maintenance in electricity generation in electric power systems. The model also has flexibility to overcome current challenges such as scalability and adaptability. The model is verified in illustrating changes in real-time and overall health condition with respect to considered anomalies by testing through actual and artificial data.


2009 ◽  
Vol 9 (4) ◽  
pp. 361-379
Author(s):  
Lu Zheng ◽  
Marvin Zelen

This paper proposes a new distribution-free statistical method for testing hypotheses about covariates for survival data having simultaneously right-, left- and interval-censored survival times. The new test is motivated by the analogue between urn sampling and the Cox’s proportional hazard models. Investigations of the significance levels and power as a function of the proportion of interval-censored observations and interval length show that the test performs well for most censoring situations encountered in practice. Simulation results also suggest that there is negligible loss of power in the practical situation in which the mean interval length for interval-censored observations is less than the mean survival time. This holds even with heavy interval censoring. Comparison with the widely used Mantel’s method for comparing two groups shows that the power of the new method appears to be superior. Furthermore, the test is relatively simple to carry out and generalizes to comparing k populations as well as the testing of general linear hypothesis for arbitrary covariates.


2019 ◽  
Vol 8 (9) ◽  
pp. 1273-1281 ◽  
Author(s):  
Dong Cen ◽  
Hui Liu ◽  
Zhe Wan ◽  
Zhongjie Lin ◽  
Yanting Wang ◽  
...  

Purpose Gallbladder neuroendocrine neoplasm (GB-NEN) is a relatively rare neoplasm, accounting for 0.5% of all neuroendocrine neoplasm cases and 2.1% of gallbladder cancers. Because of the limited understanding of GB-NEN, the aim of this study was to explore the clinicopathology and survival of GB-NEN patients selected from the Surveillance, Epidemiology, and End Results (SEER) database. Methods A total of 248 GB-NEN patients from the SEER database diagnosed between 2004 and 2015 were included. Kaplan–Meier curves were used to examine the survival time. Multivariate Cox proportional hazard models were used to estimate hazard ratios with 95% confidence intervals to analyze the impact of factors on overall survival and cancer-specific survival. Results The majority of the GB-NEN patients were women (67.3%), white (77%), and married (61.7%). Most tumors were <2 cm in size (31.0%), G3 stage (25.8%), and distant SEER stage (41.1%). 62.9% and 64.5% of cases showed an absence of lymph node metastasis and tumor metastasis, respectively. Patients who received gallbladder surgery had significantly better survival outcomes (P < 0.001). However, patients who received both gallbladder surgery and lymph node resection did not have better survival outcome compared with patients who received only gallbladder surgery. Multivariate Cox proportional hazard models indicated that older age, unmarried status, large tumor size (>5 cm), and distant SEER stage were significant independent predictors for decreased overall survival time and cancer-specific survival time (P < 0.05). Conclusion Age, marital status, tumor size, and SEER stage were predictors for the survival of GB-NEN patients. Gallbladder surgery was associated with better survival, but the combination of gallbladder surgery and lymphadenectomy had no effect on survival outcomes.


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