In many agricultural areas the difference between success and failure for a farmer is primarily dependent on the cards dealt to the farmer by nature. Weather and populations of pests such as insects, and other competing species (weeds) along with many other factors can cause significant problems in a farmer's ability to produce enough to make efforts profitable. If these types of problems cannot be overcome no amount of extra work will produce enough to allow the farmer to continue. Trying to exactly quantify or even guess how all these factors will impact the farmer's efforts in a given year is impossible. However, the history of these factors over a long period of time can be used to approximately determine the ability of the farmer to make a living over a longer period than a single growing season.
For example, weather forecasting is becoming much more sophisticated. Records over many years allow meteorologists to estimate the average precipitation levels in a region with some accuracy. Records on natural disasters, such as floods, have been kept over many years and can be used to help make decisions. In any given year a farmers crops can be completely destroyed by drought or by flood. In this case, the whole farming business may be lost. Each year a farmer must invest a significant amount of money in seed, fertilizer, machinery, fuel, and other items to plant and harvest a crop. If a crop is taken in, a farmer will be paid the current price for the crop. Even in the simplest of cases this problem seems impossible to analyze.
As a simple approximation, we could view this as a gambling problem. In the simplest of circumstances, a farmer will invest some amount of money each year with a chance of losing that investment or being paid at the end of the year for a successfully harvested crop. If the investment each year is a fixed amount, the chance of losing the crop is the same each year, and the payoff is the same each year, we have a chance of analyzing the problem. Again, we have a problem that is a close relative to the Gambler's Ruin problem. In general, to solve complicated problems it is usually necessary to try to understand how to solve the simplest cases first. In the next section a simple problem that can be analyzed is presented.