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Cross-validation (statistics)

Cross-validation, sometimes called rotation estimation or out-of-sample testing, is any of various similar model validation techniques for assessing how the results of a statistical analysis will generalize to an independent data set. It is used in settings where the goal is prediction, one wants to estimate how a predictive model will perform in practice. In a prediction problem, a model is given a dataset of known data on which training is run, a dataset of unknown data against which the model is tested; the goal of cross-validation is to test the model's ability to predict new data, not used in estimating it, in order to flag problems like overfitting or selection bias and to give an insight on how the model will generalize to an independent dataset. One round of cross-validation involves partitioning a sample of data into complementary subsets, performing the analysis on one subset, validating the analysis on the other subset. To reduce variability, in most methods multiple rounds of cross-validation are performed using different partitions, the validation results are combined over the rounds to give an estimate of the model's predictive performance.

In summary, cross-validation combines measures of fitness in prediction to derive a more accurate estimate of model prediction performance. Suppose we have a model with one or more unknown parameters, a data set to which the model can be fit; the fitting process optimizes the model parameters to make the model fit the training data as well as possible. If we take an independent sample of validation data from the same population as the training data, it will turn out that the model does not fit the validation data as well as it fits the training data; the size of this difference is to be large when the size of the training data set is small, or when the number of parameters in the model is large. Cross-validation is a way to estimate the size of this effect. In linear regression we have real response values y1... yn, n p-dimensional vector covariates x1... xn. The components of the vector xi are denoted xi1... xip. If we use least squares to fit a function in the form of a hyperplane y = a + βTx to the data 1 ≤ i ≤ n, we could assess the fit using the mean squared error.

The MSE for given estimated parameter values a and β on the training set 1 ≤ i ≤ n is 1 n ∑ i = 1 n 2 = 1 n ∑ i = 1 n 2 If the model is specified, it can be shown under mild assumptions that the expected value of the MSE for the training set is / < 1 times the expected value of the MSE for the validation set. Thus if we fit the model and compute the MSE on the training set, we will get an optimistically biased assessment of how well the model will fit an independent data set; this biased estimate is called the in-sample estimate of the fit, whereas the cross-validation estimate is an out-of-sample estimate. Since in linear regression it is possible to directly compute the factor / by which the training MSE underestimates the validation MSE under the assumption that the model specification is valid, cross-validation can be used for checking whether the model has been overfitted, in which case the MSE in the validation set will exceed its anticipated value.. In most other regression procedures, there is no simple formula to compute the expected out-of-sample fit.

Cross-validation is, thus, a applicable way to predict the performance of a model on unavailable data using numerical computation in place of theoretical analysis. Two types of cross-validation can be distinguished: non-exhaustive cross-validation. Exhaustive cross-validation methods are cross-validation methods which learn and test on all possible ways to divide the original sample into a training and a validation set. Leave-p-out cross-validation involves using p observations as the validation set and the remaining observations as the training set; this is repeated on all ways to cut the original sample on a validation set of p observations and a training set. LpO cross-validation requires training and validating the model C p n times, where n is the number of observations in the original sample, where C p n is the binomial coefficient. For p > 1 and for moderately large n, LpO CV can become computationally infeasible. For example, with n = 100 and p = 30 = 30 percent of 100 C

Error in Evolution

Error in Evolution is the second album by Swedish death/thrash metal band One Man Army and the Undead Quartet. "Mine for the Taking" – 3:53 "Knights in Satan's Service" – 3:14 "Such A Sick Boy" – 3:59 "The Supreme Butcher" – 2:57 "The Sun Never Shines: – 4:03 "See Them Burn" – 5:10 "Nightmare in Ashes and Blood" – 4:52 "He's Back" – 3:45 "Heaven Knows No Pain" – 4:45 "Hail the King" – 3:15 Robert Axelsson - Bass Marek Dobrowolski - Drums Johan Lindstrand - Vocals Pekka Kiviaho - Rhythm Guitar Mikael Lagerblad - Lead Guitar Christian Älvestam - Additional vocals on "He's Back"

Egyptian Commission for Rights and Freedoms

The Egyptian Commission for Rights and Freedoms is an Egyptian human rights organisation based in Cairo. The organisation has been subject to continuous harassment by the Egyptian authorities after reporting on human rights abuses by the el-Sisi government. ECRF is one of the few human rights organisations still operating inside a country hostile to dissent and in which countless civil society organisations have been forced to close; the commission coordinates campaigns for those who have been tortured or disappeared, as well as highlighting numerous incidences of human rights abuses. Ahmed Abdallah, Chairman of the Board of Trustees. Mohamed Lotfy, Executive Director. Mohamed Sameh, International Relations Advisor. ECRF started operating in September 2013 as a membership based human rights organisation conducting trainings to activists on the basic concepts of human rights, skills of documentation of violations, strategic campaigning, legal awareness-raising; these were received by youth activists.

Believing that all human beings are capable of defending human rights in their local communities, ECRF focuses on coordinating and accompanying the activists' energy to collectively work on the pressing issues of civil, economic, or social rights. This approach aims at documenting and mitigating human rights violations, raising civil awareness and community participation in human rights and development efforts. ECRF tracks forced disappearances in the country; these have spiked since General Abdel-Fatah Al-Sisi came to power in 2013. The Commission investigates the unauthorised use of military camps in the country for the detention of civilians; these could be held outside of judicial oversight in secret military prisons. On June 2014, The Guardian published a long article on the Azouli military jail in the Suez Canal area: "Prisoners at Azouli are electrocuted and hanged naked by their tied wrists for hours until they either give up specific information, memorise confessions or until – in the case of a small group of released former inmates – are deemed of no further use to their interrogators."

On June 2017, ECRF published a detailed report on the Galaa Military Prison and described how civilian detainees are treated and interrogated by different security agencies including the national security, military police, military intelligence and referred to military trials in the Galaa court, situated inside the complex. Lawyers connected to ECRF are acting as the Egyptian legal counsel for the family of murdered Italian Giulio Regeni, whose body bearing signs of torture was found on a desert road outside Cairo on 3 February 2016. On 2 June 2015, Mohamed Lotfy, ECRF executive director, an Egyptian-Swiss National, was banned at Cairo International Airport from travelling to Germany and had his passport confiscated, he was on his way to Berlin invited by the Greens Party to participate in a discussion panel on the deteriorating human rights situation in Egypt at the German Federal Parliament. Human Rights Watch and Amnesty International have continuously called on the Egyptian authorities to lift the abusive and arbitrary travel bans.

His speech was still read at the Bundestag: "I wish i could be with you to speak on behalf of thousands who languish in inhumane conditions in jail for their political beliefs and affiliation, on whom the world knows little. My travel ban cuts a long story short, in Egypt only one voice is allowed and any critical voice is silenced. You can still hear us not because the government allows us to speak but because Egyptians continue to strive for a democratic nation that respects fundamental rights."On 25 April 2016, Ahmed Abdallah, the Chairman of the board of trustees was arrested at his home. He was accused of various charges, he was released in September 2016 after having spent 140 days in pre-trial detention. On 20 October 2016, Egyptian authorities raided the office of the ECRF in Giza. Early morning on that day, four men — claiming to be affiliated with the Investment Authority — barged into the headquarters of ECRF and began searching the office without presenting a search warrant. Upon leaving the ECRF office, the four men threatened to close down the organisation and left without physically harming anyone in the process.

In April 2018, ECRF received the annual 2018 award of Index on Censorship for Campaigning for Freedom of Expression. Selected from over 400 public nominations and a shortlist of 16, the 2018 Freedom of Expression Awards Fellows which exemplify courage in the face of censorship were awarded to ECRF from Egypt for Campaigning, the Museum of Dissidence from Cuba for Arts, Habari from DRC for Digital Activism and to Wendy Funes from Honduras for journalism. On 21 November 2018, France and Germany announced that Mohamed Lotfy, executive director of ECRF, was chosen along with 14 other human rights defenders in the world to receive the Franco-German Prize for Human Rights and Rule of Law of 2018. Ibrahim Metwaly https://www.madamasr.com/en/topic/egyptian-commission-for-rights-and-freedoms/

Álvaro Zardoni

Álvaro Zardoni is a Mexican sculptor and architect, a member of the Salón de la Plástica Mexicana since 2006. Although he studied painting and drawing in the 1970s and 1980s, he is a self-taught sculptor who began showing his work in 2000. Since he has had over thirty individual exhibitions, twenty private showings and his work has appeared in over 100 collective exhibitions, he specializes in small bronze sculptures which focus on the human face, always male, expressing something emotional and/or psychological. Objects common, are added to the piece to reinforce the main theme of the work, for example the addition of coins on the foreheads of pieces of the Cyclops collection, he was born in Colonia Roma of Mexico City. From his earliest childhood he knew he wanted to be an artist.”He studied drawing and painting at the Irene Lidroth workshop from 1975 to 1981 than again from 1983 to 1988. From 1981 to 1982 he lived in the state of Michigan, he earned his bachelor’s in architecture from the Universidad Anáhuac in 1987.

In addition to his work in art, he worked in a number of projects. In 1987 who worked at the design workshop Associates in Lomas de Chapultepec. From 1988 to 1991 he worked with the audiovisual department at the Universidad Anáhuac and gave classes in architecture. From 1988 to 1996 he worked independently on architectural projects and with firms in the far west of Mexico City. From 1992 to 1993 he was an assistant in art direction and stage sets for IMAX, Filmcore and Cineconcepto. From 1996 to 2002 he was a project director with the Linea de Tierra company in Lomas Altas, Mexico City. From 2003 to 2008 he worked as a design assistant for the Brigada Plástica in Colonia Roma. Since 2009, he has been a partner with the Mijangos-Zardoni Studio which works on translations and subtitles, he loves to watch people in the street. He says he likes the New York City Subway where one can see people from all different races and socioeconomic levels, he has no children. Except for a one exhibit at the Plata Restaurant in Colonia Condesa, he did not begin to exhibit his sculpture until 2000.

Since he has exhibited his work in various galleries, government spaces, cultural centers in Mexico and the United States but he has had his work shown in Argentina, Germany and Italy. He has had over thirty individual exhibitions, twenty private presentations and participated in over 100 collective exhibitions. Principle showing include Los Pinos in 1996, the Agora Gallery in New York in 2003, the Museo de la Ciudad de México in 2003, the Universidad Autónoma Chapingo in 2005, the Galería Manuel Garcia in Oaxaca in 2006, the Instituto Potosino de Bellas Artes in San Luis Potosí in 2006, the Casa de las Américas in Havana in 2007, the Galería Blanco in Saltillo in 2008 and the Secretaría de Gobernación in 2009, the Salón de la Plástica Mexicana in 2011, Rising Art and Ismos galleries in 2012, he has regular showings at the Dante Gallery in Puerto Vallarta. Private presentations include Torra Altus in Mexico City, Arte Galería in Polanco, as contributor in Leah Poller’s “unmade-bed” project in New York City, auction at the Modelo Museum of Science and Industry in Toluca, Casa de los Gitanos in Ajijic, Hotel Casa Bonita in San Miguel Allende, Maria Sicardi Studio in Mexico City and pieces created for a film called La Tregua based on the novel by Mario Benedetti.

He was admitted as a member of the Salón de la Plástica Mexicana in 2006, with his first individual exhibition there in 2007, called Cyclops. It is a series of head where the open “eye” is something that represents aspects of humanity such as envy and happiness. In one, there is a coin, his work can be found in private collection in Mexico City, Los Angeles, Boston, New York, Eugene, Bogota, Buenos Aires, Vienna, Lisbon, Milan and London. He is represented in Mexico by Galleria Dante in Puerto Ismos in Mexico City. Zardoni is a self-taught sculptor learning with different materials but today works exclusively in bronze, he says that he is somewhat influenced by artist Louise Nevelson, admiring her sacrifices to become an artist, but his work is more figurative. Other sculptors he has studied include Auguste Rodin, Aristide Maillol, Camille Claudel, Josep Clarà, Josep Maria Subirachs, Arno Breker, Robert Graham and Javier Marín but he is not sure if their influence can be seen in his work, his sculpture is figurative and of small size accompanied by various commons objects to reinforce the central theme.

These include horns and accessories and hairstyles. His work has been described as academic and classic yet contemporary, his works are classic in the sense that they refer to mythology and characters from literature and legends. The addition of common objects makes them contemporary. There is always a emotional aspect to his work, his themes center on the human form with emphasis on the face, which express emotions, the soul and psychological conditions, always with humor and irony. He states that "every wrinkle expresses something and nothing is gratuitous, his faces can be somewhat androgynous but he never depicts women in his work. The general features of the faces are similar but

Glenormiston Station

Glenormiston Station most known as Glenormiston is a pastoral lease that operates as a cattle station in Queensland, Australia. Glenormiston is located about 113 kilometres west of Boulia and 335 kilometres north of Birdsville in Central West Queensland. Located at the top of the Channel Country the property shares a boundary with Marion Downs Station; the Georgina River flows through the north eastern part of the property as it journeys southward further into the channel country. The station occupies an area of 6,920 square kilometres and encompasses a variety of country from the Toko Range to the west to the floodplains to the east; the land on the property is described as being composed of open and broken downs, with river and creek flats, low limestone ridges, inferior flats and rough hills. An assessing commissioner noted that it is light carrying country, safe if not over-stocked and is excellent country for raising an fattening heavy cattle; the Wongkadjera were one of the tribes local to this area and aborigines once traded Pituri north along the Georgina River into Wangka-yutyurru country and south along the Mulligan River to the Lake Eyre system.

The creek near the homestead is named Pituri Creek and it flows into Lake Idamea. J. A. Coglan lived in the homestead in the 1890s; the station was established in 1877 along with several other well known properties in the Channel Country as pastoralists expanded westward from the grasslands at the headwaters of the Diamantina. Other properties established at the same time included Marion Downs Station, Headingly Station, Herbert Downs and Roxburgh Downs; the station was put up for auction in 1881 by Walter Douglas. At this time the station was 1,100 square miles in area and was stocked with a herd of 3000 bred Durham cattle and Hereford cattle, some horses, all plant and stock; the lands were described as open rolling downs with saltbush and cotton bush, thickly grassed with Mitchell grass and other varieties. Interspersed with open patches of gidyah and other timbers; the same year an unfortunate cook, who had only taken up the position a couple of days earlier, was killed by Aborigines in the area.

The station was sold at auction to Mr William Kelman. Flooding occurred at the station in 1885 when somewhere between 12 inches and 17 inches of rain fell over the course of a month; the Georgina River and the Diamatina Rivers both were flooded and the nearby Sandringham station was submerged. At some point prior to 1890 the station changed hands and the new owner was James Tyson who owned several other stations including Tupra, Mooroonowa,Juanbung and Bangate in New South Wales and Meteor Downs, Mount Russell and Tinnenburra in Queensland; the property was stocked with 25,000 cattle in 1890. In 1893 the region was struck by a terrible drought and the station would be thought to be lucky to be able to muster 10,000 cattle, with carcasses laying all over the property. Drought struck again to a lesser extent. Tyson died in 1898, Glenormiston was stocked with 220 horses at this time; when the station was advertised for sale in 1899 it had an area of 2,600 square miles and as adjoining Herbert Downs and Roxborough Downs stations.

The station sold that year to Collins, White and Co. along with Carnarvon and Babiloora Stations in the Warrego district. Rabbits were first seen at the station in the late 1890s with at least one permanent colony known to be located near Toco lake on the station, the furthest north that the rabbit had ventured in 1899. A meteorite, known as the Glenormiston meteorite, was found on the station by the manager Mr F. H. Story, in 1925. Story sold the object to the University of Queensland in 1926; the meteorite had a mass of 38.5 kilograms, has an irregular sub-triangular shape with convex and concave surfaces. The area was struck by drought in 1952. In 1955 the property was cut off by floodwaters. A Trans Australia Airlines aeroplane was chartered to do an airdrop of food to the property, without fresh food for a week; the North Australian Pastoral Company acquired Glenormiston in 1968. The adjoining property, Marion Downs, was acquired at about the same time. Stephen and Narda Bryce moved to the property in 2001 and Stephen was still managing the property and about ten staff in 2012.

The property has a carrying capacity of about 7000 head of cattle depending on the season. Moderate flooding was experienced at Glenormiston in 2010 following heavy rains locally and further north in the Georgina catchment. List of ranches and stations List of the largest stations in Australia

Melvins / Isis

The Melvins and Isis released a split EP on Hydra Head Records in 2010, with each band contributing two tracks. Isis' "Way Through Woven Branches" had only been available as a bonus track on the Japanese edition of their last full-length, Wavering Radiant, whilst "Pliable Foe" was exclusive to this release. Both tracks were recorded during the Wavering Radiant sessions. Meanwhile, the Melvins tracks are reworked from their release The Bride Screamed Murder, described as displaying the "dadaist/trickster tendencies of the band which has frustrated and delighted fans in equal measure since the beginning of their existence"; the album was released July 13, 2010 on CD format, with vinyl copies available a week earlier from Vacation Vinyl in Los Angeles. Pitchfork's Jess Harvell was unimpressed by Isis′ contribution to the split, stating that “Isis seem to be building to something on these songs, but the climaxes are so restrained you can miss them if you're not paying close enough attention I kept hoping Isis would let loose, offer a little chaos.

After all, the best part of Mogwai's "Like Herod" isn't the clockwork precision. As for the Melvins side, she deemed it “more of the same, but here I don't mean that in a disparaging way at all”, found that “the grooves on "I'll Finish You Off", have the same punchy dynamics the Isis tunes lack.”Isis frontman and owner of Hydra Head Records, Aaron Turner, documented the design process of the album art on his personal blog. It was released after Isis had announced their imminent dissolution, stands as their last record. However, two posthumous compilations are lined up for Isis, which would make this their third-final output. Melvins subsequently supported Isis for several dates on their farewell tour