Aalen’s additive hazards model has gained increasing attention in recently years because it model all covariate effects as time-varying. In this thesis, our goal is to explore the application of Aalen’s model in assessing treatment effect at a given time point with varying covariate effects. First, based on Aalen’s model, we utilize the direct adjustment method to obtain the adjusted survival o...

Let p ≡ 7 mod 16 be a prime. Then there are integers a, b, c, d with a ≡ 15 mod 16, b ≡ 0 mod 4, p = a + 2(b + c + d), and 2ab = c − 2cd − d. We show that there is a regular Hadamard matrix of order 4p provided that p = a± 2b or p = a+ δ1b+4δ2c+4δ1δ2d with δi = ±1. ∗This research was done during a visit of the first two authors at the University of Augsburg

This paper was motivated by the discussion held at the 2nd YMCDA meeting on the theme “What is a constructive approach in MCDA?”. On the one hand, it intends to organise some thoughts on the differences between normative, descriptive, prescriptive and constructive approaches, as well as their relation (or lack of relation) with MCDA methods. On the other hand, it intends to discuss many of the ...

We build a life cycle model of labor supply that incorporates changes along both the intensive and extensive margin and use it to assess the consequences of changes in tax and transfer policies on equilibrium hours of work. We find that changes in taxes have large aggregate effects on hours of work. Moreover, we find that there is no inconsistency between this result and the empirical finding o...

We consider the variance of the reward until absorption in a Markov chain. This variance is usually calculated from the second moment (expectation of the square). We present a direct system of equations for the variance, involving the first moment (expectation) but not the second moment. This method is numerically superior to the calculation from the second moment.