Briefly explain whether each of the following statements describes a change in supply or a change in quantity supplied. a. To take advantage of high prices for snow shovels during a snowy winter, Alexander Shovels, Inc., decides to increase output. b. The success of Pepsi's LIFEWTR and Coke's smartwater leads more firms to begin producing premium bottled water. c. In the six months following the Japanese earthquake and tsunami in 2011 , production of automobiles in Japan declined by 20 percent.

Understanding the concept of 'change in supply' is essential for analyzing market dynamics. Essentially, a change in supply refers to a shift in the supply curve either to the left or right, representing a change in the number of goods that producers are willing and able to sell at each potential price, but not necessarily at the current price level. This shift can be triggered by a variety of factors that do not relate directly to the price of the goods or services.

For instance, technological advancements can increase production efficiency, leading to a greater supply, and hence, a rightward shift of the supply curve. Conversely, events such as natural disasters can reduce the ability of businesses to produce, which decreases supply, showing as a leftward shift. The example of Japanese automakers facing production cutbacks due to the earthquake and tsunami is a real-world illustration of such a supply shift.

Distinguishing between 'change in quantity supplied' and 'change in supply' is crucial for a proper economic analysis. A change in quantity supplied is specific to a movement along the supply curve due to a change in the price of the good or service. It is a response to a change in market conditions and is represented graphically as a movement upward or downward along the unchanged supply curve.

For example, imagine a local farmer who sells more strawberries at higher prices during the peak season and less when the prices drop. This behavior does not alter the initial conditions or factors of production; it simply represents a change in the quantity of strawberries the farmer is willing to sell at different prices. The scenario of Alexander Shovels, Inc. exemplifies a 'change in quantity supplied' as the company responds to higher snow shovel prices by increasing output, moving along the same supply curve.

When we talk about 'supply curve movement', we're specifically referring to the change in quantity supplied which manifests as either an upward or downward movement along the existing supply curve. This movement is strictly confined to the quantity axis, as it occurs in response to changes in the price level of the good or service, while other factors remain constant.

An easy way to visualize this is by imagining a graph with price on the vertical axis and quantity on the horizontal axis. If a seller decides to supply more goods because the market price has increased, we observe an upward movement along the supply curve. Conversely, when the price lowers, and the seller reduces the quantity supplied, the movement is downward on the same curve. This concept is an essential tool in microeconomic analysis for understanding how businesses adjust to price changes.

In contrast to the 'supply curve movement', a 'supply curve shift' represents a change in supply. This shift is a fundamental concept in economics that signifies a new supply relationship at every price level. It could be a shift to the right, indicating an increase in supply due to factors such as technological advancements or a decrease in the costs of production. Alternatively, a shift to the left suggests a decrease in supply which may result from increased production costs, taxation, regulatory changes, or limited access to necessary resources.

A practical example includes the entrance of new firms into the bottled water market due to the success of brands like LIFEWTR and smartwater. Such an increase in the number of suppliers, as pointed out in the scenario, leads to a rightward shift of the supply curve for premium bottled water, illustrating that more of the good can be supplied at each price level.