2 Tables and charts
Experiments or surveys usually generate a lot of information from which it is possible to draw conclusions. Such information is called data. Data are often presented in newspapers or books.
One convenient way to present data is in a table. For instance, the nutrition panel on the back of a food packet:
|Nutrient Per 100g||Per 400g|
|of which sugars||2.0g||8.0g|
|of which saturates||1.1g||4.4g|
Scientific experiments often require a series of measurements taken at regular intervals. Information can be recorded as it is collected. For example, the table below resulted from an experiment to determine how quickly a cup of tea cooled down.
Tables can be laid out vertically (as in the nutrition panel) or horizontally (as in the tea experiment). Each column or row heading should indicate what is being measured and the unit of measurement. (Columns are vertical; rows are horizontal.)
A table is not merely a convenient way of presenting data. It can often facilitate comparisons and can lead to conclusions that would have been difficult to deduce from the separate data, as the next example shows.
League Table for 1977/1978 First Division
|Position||Team||Games played||Games won||Games drawn||Games lost||Goals for||Goals against||Games won||Games drawn||Games lost||Goals for||Goals against||Goal difference||Points|
|6||West Bromwich Albion||42||13||5||3||35||18||5||9||7||27||35||9||50|
|19||Queens Park Rangers||42||8||8||5||27||26||1||7||13||20||38||−17||33|
|20||West Ham United||42||8||6||7||31||28||4||2||15||21||41||−17||32|
(a) How many goals did Liverpool score at home and how many did they score away?
(b) Which team scored the most goals away from their home ground?
(c) Which was the worst team defensively away from their home gound, i.e. the team with the highest number of goals scored against them when playing away?
(d) Suggest reasons for the discrepancy between the total number of goals scored at home and the total number of goals scored away.
(a) Home – 37, Away – 28.
(b) Manchester United scored the most goals away from their home ground, 35.
(c) Chelsea let in 49 goals when away from their home ground.
(d) Possible reasons for the discrepancy could include: familiarity with the pitch, travel discomfort.
It is important to appreciate that, although you can state factual conclusions, you can often only suggest reasons. In many cases, interpretation of data depends on your own experience or on some other information not included in the table.
Use the table below to answer the following questions:
(a) What is the Body Mass Index (BMI) of a person who is 5’7” and who weighs 170 lbs?
(b) What category are they in?
(c) How much weight does a person who is 6’0” tall and who currently weighs 250 lbs have to lose in order to be in the low risk category?
(b) They are overweight.
(c) You cannot answer this question exactly using the table given. You can see from the table that a person who is 6’0” tall, weighing 190 lbs has a BMI of 26 and is low risk. So losing 60 lbs is sufficient. You also know that a weight of 200 lbs is too much to be classified as low risk, so losing 50 lbs is not sufficient. The table does not allow you to answer this question more accurately.