Introduction

This Chapter provides an overview of how statistical problems are formulated in behavioral ecology. We begin by identifying some of the difficulties that behavioral ecologists face in deciding what population to study. This decision is usually made largely on nonstatistical grounds but a few statistical considerations are worth discussing. We then introduce the subject of making inferences about the population, describing objectives in statistical terms and discussing accuracy and the general ways used to measure it. Finally, we note that statistical inferences do not necessarily apply beyond the population sampled and emphasize the value of drawing a sharp distinction between the sampled population and larger populations of interest.

Specifying the population

Several conflicting goals influence decisions about how large and variable the study population should be. The issues are largely nonstatistical and thus outside the scope of this book, but a brief summary, emphasizing statistical issues insofar as they do occur, may be helpful.

One issue of fundamental importance is whether the population of interest is well defined. Populations are often well defined in wildlife monitoring studies. The agencies carrying out such studies are usually concerned with a specific area such as a State and clearly wish to survey as much of the area as possible. In observational studies, we would often like to collect the data throughout the daylight hours – or some portion of them – and throughout the season we are studying.

Sampling throughout the population of interest, however, may be difficult for practical reasons. For example, restricting surveys to roads and observations to one period of the day may permit the collection of a larger sample size.