The TI-84-style calculator is useful for data sets, descriptive statistics and regression. This page covers lists, one-variable statistics and the most common classroom workflow.
Enter data in lists
Press STAT, choose Edit, and enter values into L1. For two-variable data, put x-values in L1 and y-values in L2.
Make sure lists are clean before entering new data. Old values can cause wrong results. Clear a list when starting a new problem.
Run 1-Var Stats
After entering one list of data, use STAT → CALC → 1-Var Stats. Select L1 if your data is in L1, then calculate.
The output includes values such as mean, sum, standard deviation, minimum, quartiles and maximum. Some classes use sample standard deviation while others use population standard deviation, so check which symbol your teacher expects.
Two-variable data
For paired data, enter x-values in L1 and y-values in L2. Both lists must have the same length.
If you get a dimension mismatch error, check for an extra missing value or an extra value in one list.
Stat plots
Stat plots can show scatter plots, boxplots and other visual data displays. They are useful for seeing patterns before choosing a regression model.
If a normal function graph disappears or looks strange, an old stat plot may still be turned on. Turn off stat plots when you return to ordinary graphing.
Check your data entry
Most statistics errors are not formula errors; they come from incorrect list entry. Re-check the first and last values, list lengths, negative signs and decimals.
For grouped or weighted data, make sure you understand whether the second list is a frequency list or a second variable.
Quick reference table
| Statistic | Meaning |
|---|---|
| x̄ | Mean or average |
| Σx | Sum of the data values |
| Sx | Sample standard deviation |
| σx | Population standard deviation |
| minX | Smallest value |
| Q1 | First quartile |
| Med | Median |
| Q3 | Third quartile |
| maxX | Largest value |