Reading Data and Studies
Charts, claims, evidence
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If you would rather use a ready-made deck such as Reading Data and Studies, we ask you for a small sum in return. For €1.29 once you get 100 flashcards, sorted into 9 categories and with notes that add to them. You start out learning instead of typing, and whatever you find missing later you add yourself.
- Cards
- 100
- Categories
- 9
- Price
- €1.29
Free, no account, no ads
What is in this deck
With this deck you learn to read a chart and a study critically: what each chart type distorts, what randomisation buys, and what a p-value and a confidence interval actually mean.
A p-value is not the probability that the hypothesis is false. A confidence interval is a statement about the procedure. Those two errors appear in published work constantly, and they are the first cards in this deck.
100 cards on reading numbers other people produced. Which chart lies about what, what a truncated axis does, and why a land-area map of votes makes empty countryside look decisive. Then study design: what randomisation buys that sample size never can, why an observational study cannot establish causation however large, and the difference between statistical and practical significance.
The last card is the one that does the most work: compared to what? It exposes a missing baseline, a missing denominator and a cherry-picked start date all at once.
The categories decide what comes up: start with “Axes” alone and add the rest when you are ready.
What you learn
- Which chart distorts what, and how axes mislead
- Correlation, confounding and reverse causation
- What randomisation buys that sample size cannot
- p-values, confidence intervals and effect size
- Publication bias, p-hacking and replication
The categories
9 categories sort the 100 cards. You can filter by category and take on what is due right now.
- Axes
- Bias
- Causation
- Chart types
- Inference
- Method
- Reading data
- Statistics
- Study design
What you get
Here are three of the 100 cards you get when you buy the deck.
Question
What does a bar chart compare well and a line chart poorly?
Answer
Categories; and change over time.
Note
Using a line for unordered categories implies a trend that does not exist.
Question
When is a pie chart defensible?
Answer
Parts of one whole, few slices, large differences.
Note
Beyond about five slices people cannot rank them by eye, which is what the chart is for.
Question
What is a histogram showing that a bar chart does not?
Answer
A distribution, with the bars touching.
Note
The x-axis is continuous, which is why the gaps disappear.
Learning with Qardbox
You see a card, you think, you turn it over and say whether you knew it. A round asks nothing more of you, and how the app works out the next date from that is on the page about FSRS-6.
What sits comes back less often, what wobbles comes back soon. You set a daily goal, and when nothing is due the app tells you exactly that instead of inventing work for you. How a round goes is shown on the learning page.
Everything stays on your device. No account, no sign-up, no ads. After the purchase the deck sits in your library like any other subject and can be studied, reordered and extended just like your own.
What it costs, and what it doesn’t
Qardbox itself costs nothing, and it stays that way. Every function is there from the start, with no subscription, no ads and no tiers; what that rests on is on the page about what it costs.
Your own cards stay unlimited, and decks from friends or from the family you read in without a limit, from a file as well. You do not need this deck in order to learn with Qardbox.
It is a shortcut: 100 checked cards for €1.29, once, with Family Sharing. The work you would otherwise do is already done. The App Store shows the price in your currency.
Common questions
Do I have to pay for Qardbox?
No. The app is free, with no subscription and no ads, and every feature is included. The only thing that costs money is a ready-made deck like this one, €1.29 once.
Could I make these cards myself?
Yes, without limit and for free. You can type them, import a file or take over cards from friends. This deck only saves you the work.
How many cards are in Reading Data and Studies?
100 cards, sorted into 9 categories.
Do I need a connection to study?
Only to download the deck. After that it lives on your device and you study offline. There is no account, and you sign in nowhere.
Which devices does this run on?
On iPhone and iPad from iOS 26, and on Apple Watch. One purchase covers the family through Family Sharing.
Is there a Qardbox for Android?
No. Qardbox is there for iPhone, iPad and Apple Watch, not for Android and not in a browser.
Other decks that go with this one
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