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What is data?
Data are facts collected for reference or analysis, and from which conclusions may be drawn
What is systematic sampling?
Systematic sampling refers to collecting data at regular intervals
What is random sampling?
Random sampling refers to the collection of data that is chosen randomly
What is a graph?
A graph is a diagram used to represent data which shows the relationship between two or more variables
Name the different types of data.
Primary
Secondary
State the 4 ways that primary data can be collected.
–Field sketching
–Taking photographs
–Conducting surveys
–Sampling
What data can be gathered through survey?
•A survey is used to gather data on people’s behaviours, needs and opinions
When will you use systematic sampling?
Systematic sampling refers to collecting data at regular intervals
What can a line graph represent?
•Line graphs use continuous data to display the relationship between two variables.
When is a compound data use?
•Compound line graphs are used when a set of data is subdivided into two or more sets of data and compared on a graph.
What is the difference between primary and secondary data.
Primary - original data collected first-hand (i.e. by you, the investigator) for investigation but secondary data that has already been collected and compiled by somebody else for another purpose
Primary - collected through fieldwork but secondary data collected from published sources
State 2 advantages and two disadvantages of primary data.
Advantages
•It is up to date (current)
•You know how the data has been collected i.e. what technique
•It only includes data that is relevant to your coursework
•It only covers your study area
•It is collected in the format that you want
Disadvantages
•The data may include some personal bias
•Data collection can be time consuming
•It can be expensive to travel to places to collect data
•It is hard to study changes over time
•Some data might be unavailable or too dangerous to collect
•Only possible to cover a small area
State two advantages and two disadvantages of secondary data.
Advantages
•You can study changes over time e.g. how population has changed over a number of years
•It can be quicker, especially if the data is on the internet
•You can study a larger area
Advantages
•You can study changes over time e.g. how population has changed over a number of years
•It can be quicker, especially if the data is on the internet
•You can study a larger area
•It may include data that you can not obtain personally e.g. salaries
•It is out of date, especially if it has been printed in a book.
•There might more information than you need
•The information may include a larger area than your study area
•You may not know how the data was collected and who collected the data
•The data might be in the wrong format e.g. in a graph and not raw figures
•It may include data that you can not obtain personally e.g. salaries
•It is out of date, especially if it has been printed in a book.
•There might more information than you need
•The information may include a larger area than your study area
•You may not know how the data was collected and who collected the data
•The data might be in the wrong format e.g. in a graph and not raw figures
Describe the way to take photographs.
Ensure that subject fills the frame
Use people or objects to indicate scale
Record time, location and description of photograph
Compare field sketch and photograph.
Both Enable information in the field to be recorded
–Records only relevant details at the field site but –Records all details at the field site
How to construct questionnaire
–Include a title and introduction
–Ask for one piece of information at a time
–Provide options for sensitive questions
–Keep it short and simple
How to conduct surveys?
–Be polite and respectful
–Greet the respondent and introduce yourself
–State the purpose of your interview
–State the estimated time needed
–Ask permission to do the interview
–Assure that responses are confidential
–Jot down responses
–Ask questions to clarify your doubts
What is the difference between simple, comparative and compound line graph.
•Only one set of data (S)
•Usually two sets of data (Comparative)
•One set of data subdivided into two or more sets of data (Compound)
What are the advantages and disadvantages of bar graphs
Advantages of bar graphs
•Allow multiple sets of data to be compared easily
•Large data sets can be used
•Patterns can be easily observed
Disadvantages of bar graphs
•Trends are difficult to predict
•Only use discrete data
•Change over time cannot be mapped
What is the advantage and disadvantage of random sampling
–Advantage - No human bias in selection
–Disadvantage - The points may not cover all parts of a varied area
State the steps to draw a histogram.
•Histograms show distribution or frequency of data.
•The x-axis shows the range of values. The values do not overlap.
•The y-axis shows the frequency.
•Histograms are presented without spaces in between the bars.
What are the advantages and disadvantages of pie charts
Advantages of pie charts
•Easy to interpret
•Show percentage total for each category
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Disadvantages of pie charts
•Value of the actual data number is unknown
•Unable to show change over time
•Unable to include too many categories
•Comparison of two data sets is difficult
State the advantages and disadvantages of systematic sampling
•Advantage - Provides more complete coverage of an area
- Essential because it is sometimes not
possible to collect data about the total
population
•Disadvantage - Sample may miss variations and result in bias.