Calamine brass Calamine brass Calamine brass is brass produced by a particular alloying technique using the zinc ore calamine directly, rather than first refining it to metallic zinc. Direct zinc smelting appears to have been unknown in Europe until the mid-18th century, even though the alloyed calamine brass was in use for centuries, and metallic zinc was produced directly via reducing-atmosphere smelting in India and China from the 12th century CE onwards. Brass is an alloy of copper and zinc and, when it was first developed, methods for producing metallic zinc were unknown. Metallurgists wishing to produce brass thus used calamine (actually
Average variance extracted heterotrait-monotrait ratio (HTMT). Related coefficients are tau-equivalent reliability (formula_7; traditionally known as "Cronbach's formula_8") and congeneric reliability (formula_9; also known as composite reliability) which can be used to evaluate the reliability of tau-equivalent and congeneric measurement models, respectively. Average variance extracted In statistics (classical test theory), average variance extracted (AVE) is a measure of the amount of variance that is captured by a construct in relation to the amount of variance due to measurement error. The average variance extracted was first proposed by Fornell & Larcker (1981). The average variance extracted can be calculated as follows: Here, formula_2 is the