A hockey stick graph or hockey stick curve is a graph, or curve shape, that resembles an ice hockey stick, in that it turns sharply from a nearly flat "blade" to a long "handle".
In economics, [1] [2] marketing, [3] and dose–response relationships, [4] [5] a hockey stick graph is one in which the "blade" is near zero (hugging the floor) before the graph turns upward to a long nearly straight increasing section. By contrast, in climate science, the well-known hockey stick graph (global temperature) describing 1000 years of global or hemispheric temperature has the "handle" horizontal and "blade" turning upward. [6] This difference of viewpoint is remarked on in a 2020 novel about climate change:
Insurance companies in a panic at last year's reports. Pay-outs at about one hundred billion USD a year now, going higher fast, as in hockey stick graph. Insurance companies insured by re-insurance. These now holding short end of stick (tall end of stick?).
— Kim Stanley Robinson, The Ministry for the Future: A Novel
A scalpel, lancet, or bistoury is a small and extremely sharp bladed instrument used for surgery, anatomical dissection, podiatry and various arts and crafts. Scalpels may be single-use disposable or re-usable. Re-usable scalpels can have permanently attached blades that can be sharpened or, more commonly, removable single-use blades. Disposable scalpels usually have a plastic handle with an extensible blade and are used once, then the entire instrument is discarded. Scalpel blades are usually individually packed in sterile pouches but are also offered non-sterile. Double-edged scalpels are referred to as "lancets".
A blade is the portion of a tool, weapon, or machine with an edge that is designed to puncture, chop, slice or scrape surfaces or materials. Blades are typically made from materials that are harder than those they are to be used on. Historically, humans have made blades from flaking stones such as flint or obsidian, and from various metal such as copper, bronze and iron. Modern blades are often made of steel or ceramic. Blades are one of humanity's oldest tools, and continue to be used for combat, food preparation, and other purposes.
The temperature record of the last 2,000 years is reconstructed using data from climate proxy records in conjunction with the modern instrumental temperature record which only covers the last 170 years at a global scale. Large-scale reconstructions covering part or all of the 1st millennium and 2nd millennium have shown that recent temperatures are exceptional: the Intergovernmental Panel on Climate Change Fourth Assessment Report of 2007 concluded that "Average Northern Hemisphere temperatures during the second half of the 20th century were very likely higher than during any other 50-year period in the last 500 years and likely the highest in at least the past 1,300 years." The curve shown in graphs of these reconstructions is widely known as the hockey stick graph because of the sharp increase in temperatures during the last century. As of 2010 this broad pattern was supported by more than two dozen reconstructions, using various statistical methods and combinations of proxy records, with variations in how flat the pre-20th-century "shaft" appears. Sparseness of proxy records results in considerable uncertainty for earlier periods.
A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. Antagonist drugs interfere in the natural operation of receptor proteins. They are sometimes called blockers; examples include alpha blockers, beta blockers, and calcium channel blockers. In pharmacology, antagonists have affinity but no efficacy for their cognate receptors, and binding will disrupt the interaction and inhibit the function of an agonist or inverse agonist at receptors. Antagonists mediate their effects by binding to the active site or to the allosteric site on a receptor, or they may interact at unique binding sites not normally involved in the biological regulation of the receptor's activity. Antagonist activity may be reversible or irreversible depending on the longevity of the antagonist–receptor complex, which, in turn, depends on the nature of antagonist–receptor binding. The majority of drug antagonists achieve their potency by competing with endogenous ligands or substrates at structurally defined binding sites on receptors.
Stephen McIntyre is a Canadian mining exploration company director, a former minerals prospector and semi-retired mining consultant whose work has included statistical analysis. He is best known as the founder and editor of Climate Audit, a blog devoted to the analysis and discussion of climate data. He is most prominent as a critic of the temperature record of the past 1000 years and the data quality of NASA's Goddard Institute for Space Studies. He is known in particular for his statistical critique, with economist Ross McKitrick, of the hockey stick graph which shows that the increase in late 20th century global temperatures is unprecedented in the past 1,000 years.
A kitchen knife is any knife that is intended to be used in food preparation. While much of this work can be accomplished with a few general-purpose knives – notably a large chef's knife, a tough cleaver, a small paring knife and some sort of serrated blade – there are also many specialized knives that are designed for specific tasks. Kitchen knives can be made from several different materials.
Richard A. Muller is an American physicist and emeritus professor of physics at the University of California, Berkeley. He was also a faculty senior scientist at the Lawrence Berkeley National Laboratory. In early 2010, Muller and his daughter Elizabeth Muller founded the group Berkeley Earth, an independent 501(c)(3) non-profit aimed at addressing some of the major concerns of the climate change skeptics, in particular the global surface temperature record. In 2016, Richard and Elizabeth Muller co-founded Deep Isolation, a private company seeking to dispose of nuclear waste in deep boreholes.
In probability theory and statistics, the probit function is the quantile function associated with the standard normal distribution. It has applications in data analysis and machine learning, in particular exploratory statistical graphics and specialized regression modeling of binary response variables.
A straight razor is a razor with a blade that can fold into its handle. They are also called open razors and cut-throat razors. The predecessors of the modern straight razors include bronze razors, with cutting edges and fixed handles, produced by craftsmen from Ancient Egypt during the New Kingdom. Solid gold and copper razors were also found in Ancient Egyptian tombs dating back to the 4th millennium BC.
In statistics and numerical analysis, isotonic regression or monotonic regression is the technique of fitting a free-form line to a sequence of observations such that the fitted line is non-decreasing everywhere, and lies as close to the observations as possible.
The dose–response relationship, or exposure–response relationship, describes the magnitude of the response of an organism, as a function of exposure to a stimulus or stressor after a certain exposure time. Dose–response relationships can be described by dose–response curves. This is explained further in the following sections. A stimulus response function or stimulus response curve is defined more broadly as the response from any type of stimulus, not limited to chemicals.
Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records. These reconstructions have consistently shown a slow long term cooling trend changing into relatively rapid warming in the 20th century, with the instrumental temperature record by 2000 exceeding earlier temperatures.
An ice hockey stick is a piece of equipment used in ice hockey to shoot, pass, and carry the puck across the ice. Ice hockey sticks are approximately 150–200 cm long, composed of a long, slender shaft with a flat extension at one end called the blade. National Hockey League (NHL) sticks are up to 63 inches long. The blade is the part of the stick used to contact the puck, and is typically 25 to 40 cm long. Stick dimensions can vary widely, as they are usually built to suit a particular player's size and preference. The blade is positioned at roughly a 135° angle from the axis of the shaft, giving the stick a partly 'L-shaped' appearance. The shaft of the stick is fairly rigid, but is slightly elastic to improve shot performance.
In pharmacology, Schild regression analysis, based upon the Schild equation, both named for Heinz Otto Schild, are tools for studying the effects of agonists and antagonists on the response caused by the receptor or on ligand-receptor binding.
Jan Esper studied geography at the University of Bonn, where he later earned his doctorate. After a postdoc position at Columbia University in New York City, he continued his work on dendrochronology at the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), and qualified as a professor at the University of Bern. In 2018, Esper became a member of the Academy of Sciences and Literature. Since 2010, he has been a professor at the Department of Geography at Johannes Gutenberg University Mainz.
A plot is a graphical technique for representing a data set, usually as a graph showing the relationship between two or more variables. The plot can be drawn by hand or by a computer. In the past, sometimes mechanical or electronic plotters were used. Graphs are a visual representation of the relationship between variables, which are very useful for humans who can then quickly derive an understanding which may not have come from lists of values. Given a scale or ruler, graphs can also be used to read off the value of an unknown variable plotted as a function of a known one, but this can also be done with data presented in tabular form. Graphs of functions are used in mathematics, sciences, engineering, technology, finance, and other areas.
Malcolm K. Hughes is a meso-climatologist and Regents' Professor of Dendrochronology in the Laboratory for Tree-Ring Research at the University of Arizona.
The Hockey Stick Illusion: Climategate and the Corruption of Science is a book written by Andrew Montford and published by Stacey International in 2010, which promotes climate change denial.
The Wegman Report was prepared in 2006 by three statisticians led by Edward Wegman at the request of Rep. Joe Barton of the United States House Committee on Energy and Commerce to validate criticisms made by Stephen McIntyre and Ross McKitrick of reconstructions of the temperature record of the past 1000 years, in particular the reconstructions by Mann, Bradley and Hughes of what had been dubbed the hockey stick graph.
The North Report was a 2006 report evaluating reconstructions of the temperature record of the past two millennia, providing an overview of the state of the science and the implications for understanding of global warming. It was produced by a National Research Council committee, chaired by Gerald North, at the request of Representative Sherwood Boehlert as chairman of the U.S. House of Representatives Committee on Science.
The hockey-stick graph, which shows a magnificent turnaround in our business starting tomorrow, is familiar to all. This is partly the fault of marketing managers who, by nature, tend to be optimists; but it is also the fault of top management, who will not accept any project that promises less than spectacular results.
The long handle of the hockey stick is the sharp increase in the debt in the 1980s and 1990s. The part of the hockey stick that you hit the ball or puck with represents slower increases ...
As usual, industry pundits are trotting out their all-purpose hockey-stick graphs to show that home networking will soon be a huge market.
The hockey stick regression method is a convenient method to estimate safe doses, which is a kind of regression method using segmented lines.
A simplified model in which a toxic substance is activated and deactivated in separate and simultaneous reactions is presented and the dose response curve implied by the model is deduced. This curve has the general form of a hockey stick, with the striking part flat or nearly flat until the dose administered saturates the deactivation system, after which the probability of a response rises rapidly.
The resulting temperature curve sloped gently downward for most of the millennium (the handle of the hockey stick), then rose sharply into the 20th century (the blade) ...