Data dives
Real data. A real question.
You find the answer.
Each dive starts with a question about something real: earthquakes, rats, the air you breathe, what your school pays. You guess first, look at one chart, then test your guess yourself. About 30 minutes each. You need paper, a pencil, and a browser.
1Your guessWrite down what you think before you see any data.2LookRead one chart and find out what it shows.3Try itOpen the same data in the pool and test your guess yourself.4Say itWrite one sentence: what you think, why, and how you checked.5What you foundCheck your numbers, and learn the name for what you just found.
New to the pool? Take the tour first.
The pool: a quick tour22 dives · four levels
01Read a chart
level 1 of 4 · 5 dives
What does this chart show, and what does it leave out?
1.12,508earthquakes in one year2,508 earthquakes. Can you spot the big ones?The answer is in the file. Finding it is another story.1.215council districtsCan a chart make a small difference look huge?Same numbers, two charts, two very different stories.1.378bad-air days in LAIs 78 bad-air days a lot?A number means nothing until you compare it to something.1.420entries on the city's tree listWhat is the most common tree on LA streets?The city keeps a list of every spot on its streets where a tree grows, or could.1.512kinds of 311 requestIs half of 311 really about old couches?A donut chart answers one question well. Try it on a second one.
no dive at this level matches
02Ask who counted
level 2 of 4 · 6 dives
Every number was counted by someone or something. Who counted, and how?
2.15New York boroughsWhich part of New York has the most rats?The city has numbers. The question is what they count.2.25boroughs, two ways to count ratsCan the city check its own rat numbers?The city counts rat calls, and it also sends inspectors. Do the two agree?2.37days of the weekDo rats take the weekend off?Some patterns have a reason. Some are just luck. How can you tell?2.4365days of 311 requestsDid all of LA stop reporting problems for a day?One strange Saturday, and what really happened.2.567years of one machineCan one machine on one mountain be trusted?Some data jumps around. Some barely wobbles. The difference tells you something.2.68school jobs on one chartWhat does a school job actually pay?Two true answers can be very far apart.
no dive at this level matches
03Compare and choose
level 3 of 4 · 7 dives
The same data can tell different stories. How you slice it changes the answer.
3.113215-year slices of one recordDid global warming stop in 1998?One temperature record, and a lot of ways to slice it.3.212months of 311 requestsWas September a normal month for LA's 311?A monthly report says yes. You might know better.3.333years of dataDoes carbon dioxide help us find planets?Two things can rise together without one causing the other.3.41,500311 requests on one mapWhere do LA's 311 requests really cluster?A map made of six-sided tiles. Change their size and see what happens.3.558California countiesDoes most of California breathe bad air?A shaded map of the state looks alarming. Look closer.3.629groups of teenagersWhich students are struggling most?Two adults, two different answers. Can they both be right?3.769colleges near WhittierDoes a more expensive college pay off?Two adults give you opposite advice. The data says something neither expected.
no dive at this level matches
04Find what's missing
level 4 of 4 · 4 dives
Sometimes the most important part of the data is the part that is not there.
4.158California countiesDoes a blank spot on a map mean clean air?A report calls six counties clean. Find out why they look that way.4.28bands of the planetIs every part of Earth warming?The planet's average is going up. Does every region agree?4.330years of earthquakesAre earthquakes in Southern California slowing down?A few quiet years in a row. Is that a trend, or luck?4.45,981planets found so farAre planets like Earth rare?We have found thousands of planets and none like Earth. What does that tell us?
no dive at this level matches