The Large Data Set – Murder Mystery
A meteorologist has been killed! Use the large data set (found here) to answer the questions and reveal
information about the murder!
Who?
Use a simple random sample, of size ten, to work out an estimated mean for the mean daily (air)
temperature in the following locations:
• Beijing May-Oct 2015;
• Perth May-Oct 2015;
• Leuchars May-Oct 2015.
Compare your results. Which city had the highest mean daily (air) temperature? Write down the values
you use and your mean.
• If the answer is Beijing, the murderer was Mr Brown.
• If the answer is Perth, the murderer was Ms Pink.
• If the answer is Leuchars, the murderer was Dr Blue.
When?
a. Look through the data set. List all the units that measure discrete variables. The number of units
which satisfy these criteria gives the day of the month the murder took place.
b. Daily mean total cloud is measured in oktas. How many values can an okta take?
The answer gives the month of the murder.
c. Calculate the overall mean daily visibility, , and the standard deviation, , for Hurn May-Oct
1987, giving your answers correct to the nearest whole number.
Using the rounded solutions, the value of + – 236 gives the year of the murder.
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Where?
The location of the murder is one of the locations given in the large data set. The police investigation was
disrupted when the location was hit by a day of unusually strong winds in the month after the murder.
Where did the murder take place?
Why?
whisker plot for the daily mean total cloud in oktas.
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The Large Data Set – Murder Mystery
In the table below, the intersection of the correct statements will give the motive for the murder. The
motive was that…
There is a greater There is a greater The spread of total
spread of total spread of total cloud cloud in Heathrow is
cloud in Camborne in Heathrow than the same as that in
than Heathrow. Camborne. Camborne.
On average, the total ...the murderer was
…the victim did not ...the victim knew that
cloud was higher jealous that the victim
know what an okta 1 knot was roughly
in Camborne than knew what an okta
was. 1.15mph.
Heathrow. was.
...the victim knew ...the murderer was angry
On average, the total
...the victim knew they couldn’t compare
cloud was lower
that 1 mph was always be greater the daily total sunshine
in Camborne than
roughly 0.87 knots. than or equal to mean between Cambourne and
Heathrow.
windspeed. Perth.
On average, the total ...the murderer was ...the murderer didn’t
...the victim knew
cloud was the same jealous the victim know that over 95%
that Dm stands for
in Camborne and knew what that tr relative humidity is likely
decametres.
Heathrow. stands for trace. to mean mist or fog.
How?
Answer the following questions and pick the corresponding letters from the grid. The letters will need
to be unscrambled to reveal the murder weapon.
1. The letters tr stand for trace. Trace rainfall is less than how many millimetres?
2. Calculate the median daily mean temperature for Heathrow from May – October 1987.
3. Find the range of the mean air temperature for Beijing from May – October 1987.
4.
5.
A H K M E F R G U I N
0.84 14.2 0.53 0.1 27.9 0.05 0.58 0.81 0.47 14.5 0.80
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