One example of false cause and effect is using the scientific observation that increased temperature correlates with increased pressure to make the assumption that temperature causes pressure. Another example is observing that the speed of a windmill is faster when the wind is faster and assuming that the windmill is the cause of the faster wind.
Types of false cause and effect typically fall into three categories: reverse causation, bidirectional causation and the common-causal variable. Reverse causation refers to noting two related events, A and B, where A causes B but a person assumes that B is causing A. For example, noting that a hot oven contains hot food can lead to the incorrect assumption that the hot food caused the oven to become hot, rather than that the hot oven caused the food to become hot.
The bidirectional causation logical fallacy occurs when both A causes B and B causes A, but the assumption of effect is that only A causes B or only B causes A. In the common-causal variable of false cause and effect, the relationship between A and B is assumed without considering the presence of a third variable. This type of fallacy is sometimes explained by the sentence, "Correlation is not equal to causation." For example, using the observation that both obesity and CO2 levels have increased since the 1950s to conclude that CO2 level increases caused the increase in obesity is a common-causal variable fallacy. A third variable may explain both increases.