人真是有拖沓的毛病,特别是把有意思的东西想完了之后甚至都懒得动手做。BLOG的草稿里堆了好多,决定还是先贴出来一些,等有空了再填。
谈谈生活 2009-09-09
鸡肉是最没有味道的,所以总要放在调料里泡上几个小时才能入味。周三下午的课总是很伤感,又会有一个星期不见好多的教授。Grimshaw总是很sensitive,老是怀疑自己教得不好,虽然大家都听得兴高采烈。
**进化的理性作用 **2009-05-31
理性主义者常常宣称,进化已经产生了智能,因此完全可以不依赖于自然选择的进化而经由理性的逻辑推理进行设计,找出最适应的方法。这一想法的狂妄之 处在于忽视了理性的逻辑推理不是独立于进化而存在的,他本身是由进化所产生,因此不会是永久可靠,也自然不会是“找出最适应”的最优办法了。同时,定义最 优的约束条件本身就是困难的,这也使得由理性推导来获得最适应族群是更加困难的。
但是,这样的论断并没有否定理性决定最适应的可能性。
公共服务的效率 2009-06-04
记得在20世纪的科幻小说中,通常描述的情景是包括公共可视电话亭(Space Odyssey Series),发达的公共自行道交通,通用的货币单位。在近一些的科幻小说中,更存在一位无处不达的计算机先知(Ender’s Game)。
然而,这一些的公共设施并没有成为现实。研究为何19世纪末20世纪初是由公共设施主导这一现象,会有助于了解21世纪初的这一个人化趋势的来源和走向。19世纪末到20世纪初建造的公共设施包括公路、铁路、电网、固定电话网、加油站,输气线路等。
One problem about nowadays visual word based image retrieval system is to generate visual word set. Visual word set tend to be big (~50k), different cluster methods such as approximate k-center, affinity propagation are applied. However, the process is somehow periodical. Imagine you are an engineer in Flickr who roll out the new image retrieval system, and you generated visual word set based on yesterday’s Flickr photo set; but today, there are 200k more photos just uploaded to Flickr, at least you have to monthly generate visual word set in order to avoid mis-classify new visual word in new photo.
In today’s real-time world, the method looks like old fashion. The need is to add new visual word as soon as new photo is uploaded. The problem is, how we know a visual word is “new”? Though it is very obvious for us or computer to judge if a text word is new or not (or not so obvious for computer ie. wrong spelling?), visual word is hard. Maybe we can put some threshold for the k-NN visual word search and claim that the new query which similarity to the nearest neighbor below certain bar is a new visual word. But it is very unlikely the naive method can work in real world. The similarity measurement is very tricky part, maybe the query is not a new visual word at all, maybe it is just an old visual word under very different illumination. If that is the case, another naive method can be suggested. We may want to measure the difference between the 1st nearest neighbor and 2nd nearest neighbor. If the similarity of the query to 1st and 2nd NN are relatively the same, we may argue it is a new visual word because in high-dimensional Euclidean space, two random points tend to have relatively the same distance. The 2nd naive method is still not so persuasive because one can argue that the approximation method is very arbitrary.
Though I cannot provide more evidence to support this, but it may work to apply sparse analysis to filter out new visual words. Let’s imagine that we try to get a representation from exist word list A: y=Ax and minimize | x | _{L1}. And the SCI (sparsity concentration index) can give good indication about if a query is new visual word or not. |
大部分人已经清楚地知道,股份在公司合作中具有重要的作用,大家都明了的有这样几种:激励,利益捆绑,决策,利益分配。在前几天和朋友的谈话中,他说不希望他自己公司股份说得太明白,大家需要钱就从公司拿就可以了,这样对大家都好。在不上市的年代里,似乎私人所有(Private-Hold)的公司中,股份显得无足轻重了。
但是,现代公司架构的股份制产生于公开交易市场之前。这样做是有道理的,首先,与常识相反,股份制将个人目标与公司目标分离开了。公司作为一个理性人,首要目的是追求高回报;而大部分个人追求的是生活的舒适性。在支出方面,两者有着严重的对立。公司一方,会想方设法减少支出,以获取更高的利润空间;个人一方,更情愿通过增加支出获得更好的生活体验。也就是说,作为理性的公司,衡量回报的标准是金钱,而个人衡量回报的标准是生活体验。
想象不通过股份方式建立起来的这样一种激励方式:公司高层可以自由支配公司花销满足个人需要。这样混乱的结果就是作为个人无法再分辨服务对象的目标,而造成大量不应有的开销。看看国内的发票报销制度,抛开其避税的初衷不谈,这样一个畸形的激励制度造成了许多可见的可避免的开销。
而股份制度提供了一种将个人目标和公司目标分开的激励手段。通常,股份制度的现金返还方式有这样的几种:公开市场转手,年度分红,公司回购。公开市场转手虽然与公司表现有关,但是并不影响管理层的运行。分红模式将个人利益与公司利益一致化。只有公司回购提供了一种个人与公司博弈的场景。而其他的激励制度,无论是自由支配花销还是发票报销,其实质都是提供一种个人与公司博弈的途径。而这样一种博弈,尤其是高层与公司的博弈,对于公司一方是不利的。
合理的股份激励避免了这种博弈情况,因此协调了公司与个人的关系,分隔了两者的目标。这种专业化,也为以后的管理层与股东分离提供了基础,保证了公司的长期发展。