7-8 Digital Technologies: Analysing and visualising data Hangman

The 27 key terms

1=SUM(B2:B10)

A formula that adds up all the numbers in a range of cells. The colon means 'from B2 to B10'. The AutoSum button can type it for you.

2=AVERAGE(B2:B10)

A spreadsheet function that adds up the numbers in cells B2 to B10 and divides by how many there are, to find the mean (the typical value). It is not the total.

3=MIN(range) and =MAX(range)

MIN finds the smallest (lowest) value in a range of cells and MAX finds the largest (highest) value. For example, =MAX(B2:B10) shows the top score in cells B2 to B10.

4=COUNT(B2:B10)

A spreadsheet formula that counts how many cells in the range B2 to B10 contain numbers. It ignores cells with text or empty cells.

5=IF(test, value_if_true, value_if_false)

Checks a test, like B2>=50. Shows the second value if the test is true and the third if it is false. Text results go in quotes, e.g. =IF(B2>=50,"Pass","Fail").

6=COUNTIF(range, criteria)

Counts how many cells in a range match a value or condition, such as "Yes" or ">10". Example: =COUNTIF(C2:C30,"Yes") counts every Yes in C2 to C30.

7=SUMIF(range, criteria, sum_range)

Adds only the numbers in sum_range whose matching cell in range meets the criteria, such as the total of all sales for one category.

8cell formatting

Changing how a cell looks, such as currency, decimal places, bold or column width, without changing the value stored inside it. For example, 5 can show as $5.00.

9query

A saved question asked of a table. It shows only the fields and records that answer it, as a new view, and leaves the original table unchanged.

10SELECT Name, Score FROM Students

A query that lists the fields to show. Only Name and Score appear, in that order, so other columns are left out. SELECT * shows every field.

11WHERE Score > 80

A criterion that limits a query to records where the condition is true, so only Score values above 80 are shown. Compare with =, <>, <, >, <=, >=. Text goes in quotes.

12AND / OR

AND needs both conditions to be true, like Year = 7 AND Score > 80. OR needs at least one to be true, like Pet = "Cat" OR Pet = "Dog". They let a query match several conditions at once.

13Like "S*"

A query criterion where the * wildcard stands for any characters, so it finds text that starts with S. Like "*s" ends with s and Like "*at*" contains at.

14ORDER BY Score DESC

Sorts query results by the Score field from highest to lowest. Use ASC for lowest to highest. Add a second field after a comma to sort ties, like ORDER BY Score DESC, Name.

15aggregate function

A query function like COUNT, SUM, AVG, MIN or MAX that looks at many records and gives one answer, such as how many records match or the average of a field.

16data representation

A way of showing the same data, such as a table, list, picture, symbol or chart. You choose the one that best suits your purpose and your audience.

17pattern, trend, outlier

Look for patterns and trends in data, like highest, lowest, going up or down. An outlier is a value that stands out from the rest. Compare groups to see differences.

18Choosing the right chart

Pick the chart that matches your question: a bar chart to compare categories, a line chart for change over time, and a pie chart for parts of a whole.

19bar chart

A chart that uses bars to compare amounts in different categories. Select the labels and values, then choose Insert chart. Column charts have upright bars; bar charts lie sideways.

20line chart

A chart that joins points with a line to show how a value changes over time. Time goes along the bottom axis, so you can see if the trend goes up or down.

21pie chart

A circle chart split into slices. Each slice shows how big one part is compared with the whole, often as a percentage. All the slices add up to 100%.

22scatter graph

A chart that plots each record as a point using two number columns, one on the x axis and one on the y axis, to show whether two things are related.

23Title, axis labels and legend

The parts that help a viewer read a chart: the title says the topic, axis labels name the data and units, the legend explains colours.

24Trendline

A straight or curved line fitted to the points on a chart. It shows the overall direction of the data, such as going up or down. Add it with Add Chart Element > Trendline.

25prediction

Extending a trend past the known data, such as running a trendline forward, to estimate a future value. It is an estimate, not a certainty, and gets less reliable the further ahead you go.

26misleading chart

A chart whose design, like a cut-off axis, 3D effects or a cherry-picked range, makes the data look different from what it truly shows.

27conclusion

A statement that answers a question using evidence from the data, such as numbers. It should only say what the data shows and stay within the data's limits.