Home > Topic > Variability
1 " He could see the tall, peeling yellow building at the periphery of his range of vision. But something about it struck him as strange. A shimmer, an unsteadiness, as if the building faded forward into stability and then retreated into insubstantial uncertainty. An oscillation, each phase lasting a few seconds and then blurring off into its opposite, a fairly regular variability as if an organic pulsation underlay the structure. As if, he thought, it's alive. "
― Philip K. Dick , Ubik
2 " The problem with racial discrimination, though, is not the inference of a person's race from their genetic characteristics. It is quite the opposite: it is the inference of a person's characteristics from their race. The question is not, can you, given an individual's skin color, hair texture, or language, infer something about their ancestry or origin. That is a question of biological systematics -- of lineage, taxonomy, of racial geography, of biological discrimination. Of course you can -- and genomics as vastly refined that inference. You can scan any individual genome and infer rather deep insights about a person's ancestry, or place of origin. But the vastly more controversial question is the converse: Given a racial identity -- African or Asian, say -- can you infer anything about an individual's characteristics: not just skin or hair color, but more complex features, such as intelligence, habits, personality, and aptitude? /I/ Genes can certainly tell us about race, but can race tell us anything about genes? /i/To answer this question, we need to measure how genetic variation is distributed across various racial categories. Is there more diversity _within_ races or _between_ races? Does knowing that someone is of African versus European descent, say, allow us to refine our understanding of their genetic traits, or their personal, physical, or intellectual attributes in a meaningful manner? Or is there so much variation within Africans and Europeans that _intraracial_ diversity dominates the comparison, thereby making the category " African" or " European" moot?We now know precise and quantitative answers to these questions. A number of studies have tried to quantify the level of genetic diversity of the human genome. The most recent estimates suggest that the vast proportion of genetic diversity (85 to 90 percent) occurs _within_ so-called races (i.e., within Asians or Africans) and only a minor proportion (7 percent) within racial groups (the geneticist Richard Lewontin had estimated a similar distribution as early as 1972). Some genes certainly vary sharply between racial or ethnic groups -- sickle-cell anemia is an Afro-Caribbean and Indian disease, and Tay-Sachs disease has a much higher frequency in Ashkenazi Jews -- but for the most part, the genetic diversity within any racial group dominates the diversity between racial groups -- not marginally, but by an enormous amount. The degree of interracial variability makes " race" a poor surrogate for nearly any feature: in a genetic sense, an African man from Nigria is so " different" from another man from Namibia that it makes little sense to lump them into the same category. "
3 " Technology tends toward avoidance of risks by investors. Uncertainty is ruled out if possible. People generally prefer the predictable. Few recognize how destructive this can be, how it imposes severe limits on variability and thus makes whole populations fatally vulnerable to the shocking ways our universe can throw the dice. "
― Frank Herbert , Heretics of Dune (Dune, #5)
4 " The SCID-D may be used to assess the nature and severity of dissociative symptoms in a variety of Axis I and II psychiatric disorders, including the Anxiety Disorders (such as Posttraumatic Stress Disorder [PTSD] and Acute Stress Disorder), Affective Disorders, Psychotic Disorders, Eating Disorders, and Personality Disorders.The SCID-D was developed to reduce variability in clinical diagnostic procedures and was designed for use with psychiatric patients as well as with nonpatients (community subjects or research subjects in primary care). "
― , Interviewer's Guide to the Structured Clinical Interview for Dsm-IV (R) Dissociative Disorders (Scid-D) (REV)
5 " forming the " hydrogen bond" ... is dynamic, with the exchange occurring in a few billionths of a billionth of a second. Since water molecules can " lose" two hydrogen atoms and " win" two by way of their oxygen atom, they are on average regrouped in fours, and the network of water, whether in our glass or in our cells is tetrahedral. All the same, this arrangement is not perfect in liquid water (otherwise the water would be a solid crystal), and locally there are many defects in the network. Although the motif of four water molecules is the most common in " linear" hydrogen bonds, the water molecule sometimes has a " forked tongue" with bifurcated liaisons, which creates arrangements of three or five, or even two or six molecules. This variability prevents water from being structured over a great distance and enables it to remain in a liquid state at the ambient temperature. "
6 " The heated public discourse about the frequency of false rape allegations often makes no reference to actual research. When the discourse does make reference to research, it often founders on the stunning variability in research findings on the frequency of false rape reports. A recently published comprehensive review of studies and reports on false rape allegations listed 20 sources whose estimates ranged from 1.5% to 90% (Rumney, 2006). However, when the sources of these estimates are examined carefully it is clear that only a fraction of the reports represent credible studies and that these credible studies indicate far less variability in false reporting rates." Lisak, D., Gardinier, L., Nicksa, S. C., & Cote, A. M. (2010). False allegations of sexual assualt: an analysis of ten years of reported cases. Violence Against Women, 16(12), 1318-1334. "
7 " As a child, I was fascinated by any branch of physical or biological science. Even today, I find great excitement in discovering the complexity and variability of the world we live in, getting a glimpse into the deeper reality that we mostly ignore in our everyday human activities. "