R: Mining Spatial, Text, Web, and Social Media Data

Hypothesis testing

The null hypothesis states that nothing has happened, the means are constant, and so on. However, the alternative hypothesis states that something different has happened and the means are different about a population. There are certain steps in performing a hypothesis test:

1. State the null hypothesis: A statement about the population is assumed; for example, the average mileage of cars within a city is 40.
2. State the alternative hypothesis: If the null hypothesis turns out to be false, then what other possibility is there? For example, if the mileage within the city is not 40, then is it greater than 40 or less than 40? If it is not equal to 40, then it is a non-directional alternative hypothesis.
3. Calculate the sample test statistic ...