The most commonly used surveys in urban transportation planning focus on data collected in or at
(1) households;
(2) workplace or special trip generator sites;
(3) visitor or tourist centers;
(4) vehicle intercept and external stations; and
(5) on transit lines [Cambridge Systematics, 1996c].
Two special types of surveys-panel and stated preference surveys-are used to collect travel behavior data.
One of the challenges in survey methodology is determining which of these surveys is most appropriate for the desired data.
Figure 4.4 shows the surveys most commonly used to collect the types of data shown. Several of these surveys will be discussed in the following paragraphs.