If employers use a test to try to predict future job performance, it is vital that the test have to ensure that it actually measures performance related to the job and is free from bias.

Aprice ceiling is “binding” if the price ceiling is set below the equilibrium price. suppose that the equilibrium price is $5. if a price ceiling is set at $6, this will not affect the market in any way since $5 remains a legally allowable price (since $5 < $6). a price ceiling of $6 is called a “non-binding” price ceiling. on the other hand, if the price ceiling is set at $4, the price ceiling is “binding” because the natural equilibrium price is $5 but that is no longer allowed. what happens when there is a binding price ceiling? at a price below the equilibrium price, quantity demanded exceeds quantity supplied. there is a shortage. normally, price increases eliminate shortages by increasing quantity supplied and decreasing quantity demanded. in this case, however, price increases are not allowed past the price ceiling. we therefore predict that the observed market price will be right at the price ceiling and there will be a permanent shortage. the observed quantity bought and sold will be dictated by the quantity supplied at the price ceiling. although consumers would like to buy more, there are no more units for sale

An increase in the market price of men's haircuts, from $16 per haircut to $26 per haircut, initially causes a local barbershop to have its employees work overtime to increase the number of daily haircuts provided from 20 to 25. when the $26 market price remains unchanged for several weeks and all other things remain equal as well, the barbershop hires additional employees and provides 40 haircuts per day. what is the short-run price elasticity of supply? nothing (your answer should have two decimal places.) what is the long-run price elasticity of supply? nothing (your answer should have two decimal places.)

Russell's study compared gpa of those students who volunteered for academic study skills training and those who did not elect to take the training. he found that those who had the training also had higher gpa. with which validity threat should russell be most concerned?