In reporting the scandal about the Norwegian cancer research, the NYT had the following unnerving comments:

A special feature of epidemiological studies like Dr. Sudbo’s is that they involve large numbers of patients and are unlikely to be repeated by other laboratories. Replication is considered the most reliable test of scientific quality.

The full text is here

It is a severe accusation to a scientific field (and in fact to all social science fields) in which observational studies are popular.

It seems to me that the author, Nicholas Wade, doesn’t understand the meaning of “replication,” at least in social science. He narrowly defined “replication” as “repeated by other laboratories.” We certainly won’t be able to replicate the study per se, and we may not be able to get the same numbers (e.g., odds ratios) from other studies. However, what is important in social science is that we can replicate the study findings, and that the findings are consistent in different populations and in different types of studies.

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Today Andrew Gelman in his blog complained that a Nature columnist mocked a paper published in the Science magazine. I’ve read that paper too. It is about the life course of social network in a big university. To me, the merits of the paper are the innovative method—email—they employed, and the quantification of the social network. These are very important because the social network research during past few years was neglected if not demised because of its inherent uncertainty and complexity, weak association with important outcomes such as health, and the lack of theoretical models. In a sense, this paper revives the social network research. Besides, this paper is fun to read.

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Jane Austen’s Pride and Prejudice is an eternal masterpiece, although sometimes I think the story is too naïve and, well, too light.

The story plot is simple. Matured women need husbands, and vice versa. So goes the opening sentence of the book:

“It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife.”

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雄孔雀的“尾巴”不是真正的形态学上的尾巴（真正的鸟尾是那个缩微型的帕森鼻－熟鸭的装饰尾巴），而是由背羽延长出来的“扇子”。雄孔雀的传说是本书中的亮点。因此仿照正宗的乔叟风格，即一个朝圣者的启示和教诲可以帮助其他朝圣者理解他们自己，在讨论人类进化过程中的两个主要转折点的时候，我也尤其期待孔雀加入我们追寻我们祖先的朝圣旅程。他的（我这里特指“他”而不是“她”）传说将会有助于我们更好地理解这个旅行。当然也不用说，他的传说就是一个性选择的传说。这里，那两个人类转折点是指从四肢爬行到双腿直立行走和随之而来的大脑增大。现在让我们再加入第三个转折点－－也许不是那么重要但却非常有人类特点的一个－－体毛的消失。为什么我们会变成裸猿？

晚期中新世时代，非洲有很多种猿类。为什么突然之间其中一支快速地走上了和其他猿类截然不同的进化道路－－实际上和所有其他的哺乳类都不同？是什么选择了这个猿类并让他高速行进在新奇的进化方向：首先双腿直立，然后又变的很聪明，并在某个时段褪去了全身的体毛？

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My Chinese translation of Science news:

干细胞：年轻的韩国学者如何协助揭露一个丑闻…
Sei Chong 和　Dennis Normile
《科学》，２００６年１月６日，２２页

首尔和东京－－２００５年１２月９日, 首尔大学（ＳＮＵ）的一个调查组的通告给全世界干细胞研究者以致命的一击：该调查组报告说，没有证据表明黄瑀锡及其研究组制造出任何一个其２００５年６月号《科学》杂志刊文中所描述的患者特异性的干细胞。很多韩国民众悲叹这次丑闻的揭露粉碎了韩国赢得世界科学尊重的希望。但是这次报道也强力支持了数十位匿名的韩国年轻科学家。他们在互相不相识的情况下，并肩协作并帮助媒体揭露了这次巨大的科学作伪案。

黄和其在几个美韩研究机构的协作者们发表于《科学》杂志上的两篇文章曾被誉为干细胞研究的创新性突破。一篇２００４年３月的文章报告了首例从人类克隆胚胎中培育的干细胞系。第二篇发在２００５年五月份。文章报告了能和９名脊髓损伤，糖尿病，及某免疫性疾病的病人在遗传上相匹配的１１株干细胞系。研究者们希望类似的干细胞能在今后帮助我们进一步认识很多遗传性疾病以及研制与病人遗传匹配的替代组织。

但是２００５年６月１日半夜刚过，这些希望开始破灭。有人给“ＰＤ手册” 节目的网络举报信箱发了封电子邮件。该节目是汉城文化放送公司（MBC）的一个长期的新闻调查节目。据该节目的一个编导金博雪（音译：Bo Seul Kim）说，投诉者表示他所知道的关于黄研究中存在的问题使其良知感到困惑。为了让“ＰＤ手册” 能和他联系，他用这句话来结束他的投诉信：“我希望你们不会拒绝这个获取真相的机会。”

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A fascinating research lead by Keith Chen from Penn State U reported that a gene polymorphism, SLC24A5, may shed light on the origin of light skin in Europeans. Almost all Europeans have one version of allele different from that of almost all non-Europeans, which causes only one amino acid difference in a melanin related enzyme. About 25% to 30% of genetic variations of skin color between blacks and whites can be attributed to this alanine to theronine change.

Some neo-racists hailed to this discovery, claiming that biological differences between blacks and whites do exist, and race has a deep root in biology. Most biologists, however, cautiously reminded that skin color is not race, and the fact that one small change of gene causes such a big difference in skin color between blacks and whites proves that there are so few differences between them.

So what do the findings from this skin color gene mean?

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During the last few weeks, the stem cell scandal not only has raised numerous speculations about what had happened in Dr. Hwang Woo Suk’s lab, but also has caused much agony among Korean science community.

The scandal is indeed a big deal. Thousands of reports on Dr. Hwang’s case are floating around in the Google. Thus, I will summarize three key points briefly.

First, is there an ethical lapse if Dr. Hwang knowingly used his junior researchers’ eggs? The consensus is that this behavior is inappropriate, to say the least.

Second, did Dr. Hwang fabricate data for the stunning paper published in the June 17 issue of Science? Again, it seems that the paper did miss some information about several stem cell lines, as accused by Roh Sung Il and the Seoul National University.

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I am not an economist, but I have learned that empirically, death penalty cannot deter the criminals. Data suggest that the crime rates went up and down regardless of death penalty.

However, I still strongly support death penalty. Death penalty is not a tool of reducing crime rate, but an ultimate punishment for those notorious criminals. It is based on a fair principle: blood for blood, teeth for teeth.

Some may criticize me that my rationale for advocating death penalty is not different from the thousands of years’ old Bible teaching. Yes, it is true. Given that the greed and sin of modern human beings are not different from those living in the Bible era, why should punishment be changed? Further, what kind of punishment is more suitable for those criminals than death penalty is?

It is also true that abusing the law or torturing the suspects are not rare. Some innocent people may be executed because the police have forced them to commit the charges. However, in an unjust society, eliminating death penalty won’t reverse the unfair treatments. Innocent people may still be sentenced to life time imprisoning. It has no difference from death. But lives of hardcore criminals are worthless. Trying to convert them is hopeless, and preserving their lives is wasting resource.

Death penalty is a must for a just society, except for that the execution of death penalty should be cautious.

From October 1980 to May 1981, a rare pneumonia, pneumocystis carinii pneumonia (PCP), was confirmed among 5 homosexual young men in Los Angeles, California. Symptoms also included a long period of fever, cytomegalovirus (CMV) infection and candidal muscosal infection. CDC reported these cases in June 5, 1981, and the Newsweek also made a passing mention about this new disease.

Meanwhile, in New York, at least eight cases were identified with aggressive Kaposi’s Sarcoma (KS). These cases were also young, homosexually active men.

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Social science, or social sciences, refers to a branch of science that uses scientific methods to study the behavior of human and the society. It includes language studies, psychology, econmics, anthropology, sociology, and many others. It is related to humanities.

Yes, because social science deals with unpredictable human behavior and societal movements, there is no absolutely true or wrong answer for most social problems. However, social theories are formed exactly the same way as other sciences do: first observe the phenomenon, then summarize it and form a theory, and then collect data and test the theory. It is a spiral process. The empiricism is the key in modern social science.

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