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Geographical Investigation Fieldwork – Sampling Methods
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1 Methods in Data Collection a Observation • Prior knowledge and background research forms an important backbone to strong observation
skills as they help the observer to know what to observe, when to observe and how to make sense of what is being observed.
Advantages Disadvantages
• It provides direct access to the phenomena under consideration.
• It provides real-‐time information about the phenomena being studied.
• It is complementary with other approaches e.g. interviewing or sampling to triangulate data.
• It can be very time-‐consuming and resource intensive, especially if the researcher has to work within a short time frame.
• Some phenomena require a longer period of observation e.g. human traffic flow at a tourist attraction on weekdays vs. weekends.
• Observation is susceptible to observer bias-‐ the observer may interpret his observation in a manner different from what is actually being portrayed.
• May be subjected to the ‘observer effect’ in which those who are being observed are cautious of the observer and do not behave as they normally would.
b Making Field Sketches • There are many ways to record what is being observed.
− These include making notes on maps and/ or photographs, using recording sheets, or just simply taking notes.
• It is important to select the most effective and efficient method/tool for recording what is being observed. − You should use more than one recording tool to assist your recording of information. − Making field sketches is one way of helping you to record what you observe and to further
develop observation. • When making a field sketch, you may want to do the following:
− Include location/site number, title, compass direction and date in your sketch. − Use a viewfinder (rectangular frame) to help you frame your selected viewpoint. − Divide the sketching frame into nine parts. The division makes it easier to position objects
within your sketch. − Sketch frame by frame from the background to the foreground. − Ensure your selected viewpoint covers the relevant features. − Think about the type of information you may need to include in your sketch. Ensure your
sketch is well annotated.
Geographical Investigations | Data collection and Sampling Methods 2
Example
Advantages Disadvantages
• Details which are prominent yet unimportant in photographs can be left out.
• Smaller bits of detail can be elaborated on.
• Sketching provides a broad overview of the relevant features in the place of research thus complements photographs.
• Scale of items may be altered in the sketch e.g. drawing them larger/smaller relative to other objects in the frame.
• Difficult to include important details due to the lack of drawing skills/ lack of an eye for small details.
• Important detail may be left out if the frame contains may details. e.g. vegetation in a rainforest may be too dense to be sketched accurately.
• Excess detail may be intentionally or accidentally included e.g. more litter than that present may be sketched in a study to investigate human impact on the natural environment.
c Photographs • Other than sketches, photographs can also be used to record the features on the fieldwork site
for future reference. − Annotations can be added to photographs to help highlight essential information.
Advantages Disadvantages
• They are more accurate than field sketches
• They can be good for showing data collection techniques e.g. measuring the height of trees in a forest
• They can support data collection findings e.g. they can show an example of the impacts of tourism.
• They can show temporal changes, especially if you can find historical photos.
• You can annotate and label them.
• People often include photos that are not relevant e.g. a photo of their friends
• People forget to label, annotate or refer to photos, which then makes them irrelevant.
• People often only photograph the nice things e.g. pretty view and forget the more ‘ugly’ areas that are just as important e.g. area of pollution
• They can often contains too much information e.g. people and vehicles
• Because they are two dimensional, depth can be deceptive
Geographical Investigations | Data collection and Sampling Methods 3
d Recording sheets • Recording sheets facilitate the recording of data on the fieldwork site. • Data collection is more organised when tables are included in recording sheets. • However, predetermined categories may be restrictive because data that does not fall into these
categories may not be recorded. This affects the reliability of the data. − Hence, you may choose to include a column for recording anomalies.
e Maps • Maps are an essential primary source in any fieldwork investigation because they show the
location of physical features and human activities. − Hence, even before fieldwork begins, one can infer how the physical and human
environments to be studied interact with each other.
Advantages Disadvantages • The size and scale of the feature observed or
photographed can be accurately ascertained. • Map legends can be used to confirm the identity
of the observed features. • Allows an accurate understanding of the
distribution of observed features e.g. distribution pattern of tourist amenities in a location that may not be easily observed due to the scale of the place e.g. too big
• Maps may not always be up to date and may not reflect new developments/features or old features that have been altered/removed.
• Maps are unable to temporal changes in a landscape e.g. changes in tourist density throughout a year.
• Maps are subjected to creator bias-‐ the map creator may choose to highlight certain features over others.
Geographical Investigations | Data collection and Sampling Methods 4
2 Sampling Methods • This involves selecting a specimen to be used for further analysis or study. A specimen sample
chosen should be representative of the rest. It may be random or selective sampling. i Areal sampling: sampling a predefined area e.g. a quadrat ii Linear sampling: sampling along a line e.g. a transect iii Random sampling: every unit has an equal probability of being sampled iv Systematic sampling: sampling is set at intervals selected
Advantages Disadvantages
• Useful when the study area or the population of interest is large as it provides a good estimation of the phenomena in question.
• Systematic sampling provides a better coverage of the study area than random sampling and reduces the bias involved in random sampling.
• Researcher may be biased in choosing a location to sample e.g. the most accessible location/ the location with the mild conditions e.g. cleanest, gentle slope, sheltered. This results in the lack of an accurate representation of the area of phenomena.
• Time-‐consuming if the sample size of large. • Difficult to decide on sample size that is large
enough to provide accurate representation. Method Random Systematic Definition A sample in which all elements in the
sampling frame have an equal chance of selection, and sampling is done in a single stage with each element selected independently.
A starting point is chosen in the sampling frame. Items are then picked at regular intervals. Each item has an equal chance of being selected.
Example To select a sample of size n from a population of N people, we can list all the names of the N people on slips of paper and draw n slips out randomly.
Visitors are being interviewed at a tourist attraction. Every 10th visitor that passes through the entrance is chosen.
Advantages • Analysis of data is relatively easy. • The data collected is free from
bias.
• The sample is more evenly spread out over the population.
• It is easier to conduct than other types of sampling.
Disadvantages
• It is difficult or impossible to identify every member of the population, especially if the population is large.
• We may not be able to get access to some members who have been chosen for the sample.
• There is a bias caused by the effect of periodicity of the population.
• It is not always possible to determine the size of the population in order to decide on the interval to use (e.g. every 10 visitors or every 20?)
Geographical Investigations | Data collection and Sampling Methods 5
Method Stratified Quota Definition The population is divided into non-‐
overlapping representative groups or strata according to one or more criteria. Items are selected randomly from each stratum, with the sample size being proportional to the relative size of the stratum. Hence, each item has an equal chance of being selected.
It works in the same way as stratified sampling except that the sample size is not proportional to the relative size of the stratum and the selection of the sample is non-‐random (i.e. judgement is used to select the sample based on a specified proportion).
Example In a group of 40 tourists, the nationality composition is as follows: Chinese Indian Thai Malaysian 8 6 10 16
To obtain a random sample of 20 tourists, we draw random samples from the different groups with a sample size n the same proportion as the size of each group. Chinese India Thai Malaysian (8/40) x 20 = 4
(6/40) x 20 = 3
(10/40) x 20 = 5
(16/40) x 20 = 8
Students were asked to interview 20 people concerning some problems of tourism in an area. They are given quotas to fill from specified subgroups as shown below.
Sex Age M F 20-‐30 6 10 10 31-‐40 8 41-‐50 6
The interviewer is given a free choice in picking the people to fill the quotas.
Advantages • The results of each stratum may be analysed separately, so it is convenient and usually gives more accurate estimates than simple random sampling.
• It is more likely to give a representative sample of the population.
• The cost is low. • It is faster to gather information.
Disadvantages
• It can be difficult to identify appropriate strata.
• It is time consuming. • It is more difficult to conduct and
analyse results than simple random sampling.
• It is not a good representation of the population as a whole as compared to other types of sampling.
• This method is biased as the interviewer may choose those who are easier and willing to be interviewed.
