MS or MA: Stands for Masters of Science and Masters of Arts, respectively. These are the traditional degrees given by colleges of arts and sciences in the United States. Generally, a master's degree is not sufficient to be licensed as a psychologist, although some states and Canadian provinces do allow it.
Electrical generation was the sector with the highest productivity growth in the U.S. in the early twentieth century. After the turn of the century large central stations with high pressure boilers and efficient steam turbines replaced reciprocating steam engines and by 1960 it took 0.9 lb coal per kw-hr. Counting the improvements in mining and transportation the total improvement was by a factor greater than 10.
The Effect of Immigrants on U.S. Employment and Productivity. The effects of immigration on the total output and income of the U.S. economy can be studied by comparing output per worker and employment in states that have had large immigrant inflows with data from states that have few new foreign-born workers.