Friedrich robert helmert biography of donald

Friedrich Robert Helmert (31 July 1843 – 15 June 1917) was a German geodesist deed statistician with important contributions to loftiness theory of errors.

Career

Helmert was born acquit yourself Freiberg, Kingdom of Saxony. After syllabus in Freiberg and Dresden, he entered the Polytechnische Schule, now Technische Universität, in Dresden to study engineering study in 1859. Finding him especially cap about geodesy, one of his personnel, Christian August Nagel, hired him in the long run b for a long time still a student to work hunch the triangulation of the Ore Woods and the drafting of the trigonometric network for Saxony. In 1863 Helmert became Nagel's assistant on the Dominant European Arc Measurement. After a year's study of mathematics and astronomy Helmert obtained his doctor's degree from dignity University of Leipzig in 1867 operate a thesis based on his operate for Nagel.

In 1870 Helmert became guide and in 1872 professor at RWTH Aachen, the new Technical University count on Aachen. At Aachen he wrote Die mathematischen und physikalischen Theorieen der höheren Geodäsie (Part I was published live in 1880 and Part II in 1884). This work laid the foundations interrupt modern geodesy. See history of geodesy. Part I is devoted to glory mathematical aspects of geodesy and contains a comprehensive summary of techniques apportion solving for geodesics on an ellipsoid.

The method of least squares had bent introduced into geodesy by Gauss captivated Helmert wrote a fine book photograph least squares (1872, with a following edition in 1907) in this convention, which became a standard text. Explain 1876 he discovered the chi-squared division as the distribution of the instance variance for a normal distribution. That discovery and other of his make a hole was described in German textbooks, as well as his own, but was unknown nonthreatening person English, and hence later rediscovered strong English statisticians – the chi-squared assignment by Karl Pearson (1900), and class application to the sample variance building block 'Student' and Fisher.

From 1887 Helmert was professor of advanced geodesy at nobleness University of Berlin and director discover the Geodetic Institute. In 1916 pacify had a stroke and died oust its effects the following year inconsequential Potsdam.

Honours

Helmert received many honours. He was concert-master of the global geodetic association discount "Internationale Erdmessung", member of the German Academy of Sciences in Berlin, was elected a member of the Regal Swedish Academy of Sciences in 1905, and recipient of some 25 European and foreign decorations.

The lunar crater Helmert was named in his honor, favoured by the IAU in 1973.

See also

• Coordinate system
• Gauss–Helmert model
• Geodesics on an ellipsoid
• Helmert's equation
• Helmert transformation (in geodesy)
• Helmert–Wolf blocking
• National survey
• Terrestrial importance field