Test: Methods of Data Collection - Civil Engineering (CE) MCQ

There are 6 methods for conducting the origin-destination study. The data collected from these studies help to modify or plan the pattern of the road. It also helps to compare the current and future potential of the road.

Key Points
Stages of processing of data:
Stage 1: Editing of Data

• The editing of data is a process of examining the raw data to detect errors and omissions and to correct them, if possible, to ensure legibility, completeness, consistency and accuracy. 
• The recorded data must be legible so that it could be coded later. An illegible response may be corrected by getting in touch with people who recorded it, or alternatively it may be inferred from other parts of the question.

Stage 2: Coding of Data:

• Coding is the process of assigning some symbols (either) alphabetical or numerals or (both) to the answers so that the responses can be recorded into a limited number of classes or categories.
• The classes should be appropriate to the research problem being studied.
• They must be exhaustive and must be mutually exclusive so that the answer can be placed in one and only one cell in a given category.

Stage 3: Classification of Data:

• Classification condenses the data, facilitates comparisons, helps to study the relationships and facilitates in statistical treatment of data.
• The classification should be unambiguous and mutually exclusive and collectively exhaustive.
• Further, it should not only be flexible but also suitable for the purpose for which it is sought.'
• Classification can either be according to attributes or numerical characteristics

Stage 4: Tabulation of Data:

• The tabulation is used for summarization and condensation of data.
• It aids in analysis of relationships, trends and other summarization of the given data.
• The tabulation may be simple or complex.
• Simple tabulation results in one-way tables, which can be used to answer questions related to one characteristic of the data.
• The complex tabulation usually results in two way tables, which give information about two interrelated characteristics of the data; three way tables which give information about three interrelated characteristics of data; and still higher order tables, which supply information about several interrelated characteristics of data. 

Stage 5: Using Percentages:
The tabulated data is converted into percentages and useful results are drawn from it.

Licence plate mail-out method is an origin-destination study by which data is collected to help develop trip generation and trip distribution models and to determine the potential of the present highway system and plan for new facilities.

There are 2 methods by which licence plate number of the vehicles can be obtained by Licence plate mail-out method of origin-destination study. Taking photo or video or manually recording the tag on the vehicle are the two methods of recording licence plate number of the vehicles.

Licence plate mail-out method is the origin-destination study which has no disruption to normal traffic flow because this method does not require vehicles to be stopped during the survey. The surveyor takes a photograph or video and records it without interrupting the flow of traffic.

Roadside interview method disrupts the flow of traffic. Other than that it is a very productive technique since it has a high response rate, good sampling control, and broad geographic coverage.

Traffic disruption is the primary disadvantage of Roadside interview method. This method requires more traffic control at the location of the survey. But this method provides complete information.

Mail-back postcard surveys are usually conducted using a postcard with brief questionnaire. The postcard is distributed to motorists at rest stations or at signalised intersections.

Phone surveys are usually used for Household travel survey. This method has a higher response rate than mail-back postcard survey and lower response rate than the road interview method.

Mail-back postcard surveys is usually used when traffic volume is high. This method has less traffic disruption compared to Roadside interview method.