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Visar resultat 1 - 5 av 417 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Essays on Mergers and Acquisitions and Event Studies

   Författare :Mohammad Irani; Lars Nordén; Rickard Sandberg; Neslihan Ozkan; Stockholms universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; mergers and acquisitions; event study; prediction; payment method; conditional CAPM; time-varying parameters; structural change methodology; variance; covariance; företagsekonomi; Business Administration;

   Sammanfattning : This dissertation consists of three studies on the anticipation of mergers and acquisitions (M&As) and its impact on takeover event studies. Article I investigates whether the market can anticipate both takeovers and their payment forms prior to their announcement dates. LÄS MER

3. 2. Prostate cancer incidence, treatment and mortality : Empirical longitudinal register-based studies and methods for handling missing data

   Författare :Marcus Westerberg; Rolf Larsson; Hans Garmo; Pär Stattin; Jimmy Olsson; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; statistics; mathematics; prostate cancer; missing data; survival analysis; longitudinal models; incidence; treatment; mortality; Mathematical Statistics; Matematisk statistik; Statistics; Statistik; Urologi; Urology; Epidemiologi; Epidemiology;

   Sammanfattning : The diagnostic activity for prostate cancer has increased substantially in Sweden, primarily due to increased use of prostate-specific antigen (PSA) testing in asymptomatic men, and this has led to a large increase in diagnoses. There have also been changes in the diagnostic workup, guidelines, treatment strategies, and more effective treatments have been introduced in different phases of the disease. LÄS MER

4. 3. Image Analysis in Support of Computer-Assisted Cervical Cancer Screening

   Författare :Patrik Malm; Ewert Bengtsson; Calum MacAulay; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Image analysis; cervical cancer; pap-smear; synthetic images; screening; image processing; cytometry; Computerized Image Processing; Datoriserad bildbehandling;

   Sammanfattning : Cervical cancer is a disease that annually claims the lives of over a quarter of a million women. A substantial number of these deaths could be prevented if population wide cancer screening, based on the Papanicolaou test, were globally available. The Papanicolaou test involves a visual review of cellular material obtained from the uterine cervix. LÄS MER

5. 4. On Medical Image Segmentation With Noisy Labels

   Författare :Marcus Nordström; Henrik Hult; Atsuto Maki; Fredrik Kahl; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Medical image segmentation; image segmentation; machine learning; supervised learning; label noise; Sörensen-Dice coefficient; soft-Dice; Medicinsk bildsegmentering; bildsegmentering; maskininlärning; övervakat lärande; annoteringsbrus; Sörensen-Dice koefficienten; soft-Dice; Tillämpad matematik och beräkningsmatematik; Applied and Computational Mathematics; Mathematical Statistics; Matematisk statistik;

   Sammanfattning : It is well known that data sets used for training and testing automatic medical image segmentation methods often contain a lot of label noise. Such noise affects the performance of the methods and has been subject to a lot of research. LÄS MER

7. 5. Calibration Adjustment for Nonresponse in Sample Surveys

   Författare :Bernardo João Rota; Thomas Laitila; Sune Karlsson; Risto Lehtonen; Örebro universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Auxiliary variables; Calibration; Nonresponse; principal com-ponents; regression estimator; response probability; survey sampling; two-step estimator; variance estimator; weighting; Statistics; Statistik;

   Sammanfattning : In this thesis, we discuss calibration estimation in the presence of nonresponse with a focus on the linear calibration estimator and the propensity calibration estimator, along with the use of different levels of auxiliary information, that is, sample and population levels. This is a fourpapers- based thesis, two of which discuss estimation in two steps. LÄS MER