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  2. Heckman correction - Wikipedia

    en.wikipedia.org/wiki/Heckman_correction

    The resulting likelihood function is mathematically similar to the tobit model for censored dependent variables, a connection first drawn by James Heckman in 1974. [2] Heckman also developed a two-step control function approach to estimate this model, [ 3 ] which avoids the computational burden of having to estimate both equations jointly ...

  3. Redshift - Wikipedia

    en.wikipedia.org/wiki/Redshift

    The effect is sometimes called the "Doppler–Fizeau effect". In 1868, British astronomer William Huggins was the first to determine the velocity of a star moving away from the Earth by the method. [5] In 1871, optical redshift was confirmed when the phenomenon was observed in Fraunhofer lines, using solar rotation, about 0.1 Å in the red. [6]

  4. lambda-connectedness - Wikipedia

    en.wikipedia.org/wiki/Lambda-connectedness

    The lambda-connected segmentation is a region-growing segmentation method in general. It can also be made for split-and-merge segmentation. [ 4 ] Its time complexity also reaches the optimum at O ( n l o g n ) {\displaystyle O(nlogn)} where n {\displaystyle n} is the number of pixels in the image.

  5. Angular diameter distance - Wikipedia

    en.wikipedia.org/wiki/Angular_diameter_distance

    The angular size redshift relation for a Lambda cosmology, with on the vertical scale megaparsecs. The angular size redshift relation describes the relation between the angular size observed on the sky of an object of given physical size, and the object's redshift from Earth (which is related to its distance, d {\displaystyle d} , from Earth).

  6. Lambda2 method - Wikipedia

    en.wikipedia.org/wiki/Lambda2_method

    The Lambda2 method, or Lambda2 vortex criterion, is a vortex core line detection algorithm that can adequately identify vortices from a three-dimensional fluid velocity field. [1] The Lambda2 method is Galilean invariant , which means it produces the same results when a uniform velocity field is added to the existing velocity field or when the ...

  7. Distance measure - Wikipedia

    en.wikipedia.org/wiki/Distance_measure

    Distance measures are used in physical cosmology to give a natural notion of the distance between two objects or events in the universe.They are often used to tie some observable quantity (such as the luminosity of a distant quasar, the redshift of a distant galaxy, or the angular size of the acoustic peaks in the cosmic microwave background (CMB) power spectrum) to another quantity that is ...

  8. AWS Lambda - Wikipedia

    en.wikipedia.org/wiki/AWS_Lambda

    AWS Lambda is an event-driven, serverless Function as a Service (FaaS) provided by Amazon as a part of Amazon Web Services. It is designed to enable developers to run code without provisioning or managing servers.

  9. Amazon Redshift - Wikipedia

    en.wikipedia.org/wiki/Amazon_Redshift

    Amazon Redshift is a data warehouse product which forms part of the larger cloud-computing platform Amazon Web Services. [1] It is built on top of technology from the massive parallel processing (MPP) data warehouse company ParAccel (later acquired by Actian ), [ 2 ] to handle large scale data sets and database migrations .