# Production and Costs
- "The Economics of the Lemonade Stand"
- 4 main cost measures
- Average fixed costs
- Average variable costs
- Average total costs
- Marginal costs
## The Production Process
- Input -> Production Process -> Output
- _Production function_ = the relation between inputs and the Q of outputs
- Variable Input, usually labor
- Fixed Input, usually capital
- Possible: fixed input in the short-run, but variable input in the long-run.
- Short-run = all inputs are fixed
- Long-run = all inputs are variable
## Introducing Costs
> [!tip] Definition _Marginal Product of Labor_ = the additional quantity of
> output obtained from using one more unit of labor, slope of Product of Labor
> curve
$
MP_L = \frac{\Delta Q}{\Delta L}
$
- Total Cost = Fixed Cost + Variable Cost
- Total Product Curve and Total Cost Curve are mirror to each other
> [!tip] Definition _Marginal Cost_ = the change in total cost arising from
> producing one more unit of output. slope of Total Cost Curve
$
MC = \frac{\Delta TC}{\Delta Q}
$
- Average Fixed Cost = Fixed Cost / Output
- ATC = AVC + AFC
- Marginal Cost curve crosses the lowest point of ATC curve.
- If Marginal Cost < Average Total Cost, MC is pulling down the ATC, hence ATC
is decreasing.
- If MC > ATC, MC is pulling up the ATC, hence ATC is increasing
## Conclusion to Production
- Natural Monopolies = lowering the Average Fixed Cost
- Higher marginal productivity per labor -> higher wages