Dependency measures for synthetic ED patient populations.

<p>Dependency measures for synthetic ED patient populations.</p

Target marginal modification operators.

<p>(a) Original marginal distribution, (b) Skew left, (c) Skew right, (d) Uniform, (e) Fat tail, (f) Thin tail, (g) Perturbation.</p

Results from the tail dependent joint distribution with skew, fat tail and thin tail operators.

<p>Results from the tail dependent joint distribution with skew, fat tail and thin tail operators.</p

IPF output b_IPF.

<p>IPF output b_IPF.</p

Copula-Based Approach to Synthetic Population Generation

<div><p>Generating synthetic baseline populations is a fundamental step of agent-based modeling and simulation, which is growing fast in a wide range of socio-economic areas including transportation planning research. Traditionally, in many commercial and non-commercial microsimulation systems, the iterative proportional fitting (IPF) procedure has been used for creating the joint distribution of individuals when combining a reference joint distribution with target marginal distributions. Although IPF is simple, computationally efficient, and rigorously founded, it is unclear whether IPF well preserves the dependence structure of the reference joint table sufficiently when fitting it to target margins. In this paper, a novel method is proposed based on the copula concept in order to provide an alternative approach to the problem that IPF resolves. The dependency characteristic measures were computed and the results from the proposed method and IPF were compared. In most test cases, the proposed method outperformed IPF in preserving the dependence structure of the reference joint distribution.</p></div

Output results for normal joint distribution and fat tail target margins.

<p>Output results for normal joint distribution and fat tail target margins.</p

Kendall’s rank correlation coefficients τ(X,Y).

<p>Kendall’s rank correlation coefficients τ(X,Y).</p

Lonicera vidalii Franch. et Savat.

原著和名: オニヘウタンボク科名: スイカズラ科 = Caprifoliaceae採集地: 長野県 北佐久郡 軽井沢町西部 (信濃 北佐久郡 軽井沢町西部)採集日: 1984/5/23採集者: 萩庭丈壽整理番号: JH022209国立科学博物館整理番号: TNS-VS-97220

Collection view of CBJF (Partition lines are for the example in Table 1).

<p>Collection view of CBJF (Partition lines are for the example in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0159496#pone.0159496.t001" target="_blank">Table 1</a>).</p

Results from the bimodal joint distribution with skew, fat tail and thin tail operators.

<p>Results from the bimodal joint distribution with skew, fat tail and thin tail operators.</p