Stage 8 - Q1 - 2 marks
What temperature is shown on day three?
Hint
Use the plotted point at the stated time.
Stage 8 - Q2 - 2 marks
What is the change from day zero to day one?
Hint
Subtract the earlier reading from the later one.
Stage 8 - Q3 - 3 marks
Describe the overall temperature change from the first to the last day. Did it increase every day?
Hint
Overall change and monotonic change are different ideas.
Stage 8 - Q4 - 3 marks
Find the greatest one-day increase and identify the interval.
Hint
Compare slopes over equal one-day intervals.
Stage 8 - Q5 - 3 marks
Estimate the temperature at day 2.5 using the straight segment. Is it an actual recorded measurement?
Hint
Average the adjacent readings only because the time is halfway.
Stage 8 - Q6 - 4 marks
Draw a time series graph for days 0, 1, 2, 3 with temperatures 6, 9, 11, 10°C.
Hint
Time belongs on the horizontal axis.
Stage 8 - Q7 - 4 marks
Series A has readings 8, 12, 10, 16 and series B has 10, 11, 13, 14 at equal daily intervals. Compare their overall changes and ranges.
Hint
Range and overall change happen to agree here, but use their definitions separately.
Stage 8 - Q8 - 4 marks
A plant is 10, 12, 14 and 16 cm tall on four successive days. A pupil says it will definitely be 18 cm the next day. Evaluate this conclusion.
Hint
A trend outside the observed times is a forecast.
Stage 8 - Q9 - 5 marks
Measurements at times 0, 1, 4, 5 hours are plotted at equal horizontal spacings. Explain what is misleading and how to repair the graph.
Hint
Compare the lengths of the time gaps, not the number of observations.
Stage 8 - Q10 - 6 marks
Construct two different five-day integer time series, each with mean 10 and range 8. One must rise every day and the other must not. Explain why mean and range do not determine the order of a series.
Hint
Rearranging a fixed data set preserves mean and range.