Macroeconomics the employment sector?

Question

Hi just had a problem with a particular element of this chapter, i know when you get tech adv the production function changes that is greater amount of marginal product per labour compared to before thus you can produce more with the same amount of labour ....but this is what i dont get does the labour demand curve shift out in the labour sector since MPL=w (real wage) thus the employment sector has to equilibrate at a higher level of w, increasing both level of employment and output ...if this is so is it the case for both fully flexible and fixed the model
Its just that on of my prof said one thing and another said something else and so close to exam times its anarchary trying to get hold of them
PLEASE CAN ANYONE HELP AS SOON AS POSSIBLE
THANKS

Answer 1

We know from experience that when there was technology improvements that increased the productively of labor in manufacturing, the amount of labor employed in manufacturing declined. If economics is correct then then the full general equilibrium model will predict this. The confusion arises because in econ classes problems are analyzed using partial equilibrium holding "all else constant".
You can make different assumptions about what is held constant when you change the production function of a single firm in a industry or all firms in a industry.
price
demand
price of other goods
nothing but tastes
nothing

Answer 2

Wouldn't it matter if the tech improvement was one which complimented the use of labor vs. one which substituted the use of labor (automation)? If the tech improvement used the labor input, then labor demand would increase in that industry. However, if the tech improvement was one which substituted the labor input, then labor demand would decrease. Are you sure MPL equals W? I thought this only happened in a purely competitive environment, where the firm was a "wage taker".