AP Statistics TI-84 Quick Reference Sheet-IITian Academy
TI-84+ Quick Reference Sheet — AP Statistics
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Choose 2nd → MEM → #1 About
ID: ***** ***** *****
Run DEFAULTS to reset calculator.
2nd MEM → #7 Reset → #2 Defaults → #2 Reset
- Place data in Lists: STAT → EDIT
- Engage 1-Variable Statistics: STAT → CALC → #1 1-VAR STATS
- On Home Screen indicate list: 1-VAR STATS L₁
\( \bar{x} = \text{mean} \), \( s_x = \text{sample SD} \), \( σ_x = \text{population SD} \)
\( Q_1 = \text{first quartile} \), \( \text{med} = \text{median} \), \( Q_3 = \text{third quartile} \)
\( n = \text{sample size} \)
- Place data in Lists: STAT → EDIT
- Set up plot info: STAT PLOT → #1 <ENTER>
Highlight ON and choose symbol.
XList: L₁, Freq: 1 - Graph: ZOOM #9 → TRACE
- Xscl in WINDOW controls bar width.
Integer values are easiest to read.
Must be ON to see correlation coefficient (r).
- MODE → StatDiagnostics → ON
- or CATALOG → ALPHA D → DiagnosticOn → ENTER → ENTER
(Linear, Quadratic, Exponential, Power, etc.)
- Enter data: STAT → EDIT
- Graph scatter plot: STAT PLOT → #1 → ENTER → choose ON
- Set XList = L₁, YList = L₂
- Graph: ZOOM #9
- Regression: STAT → CALC → #4 LinReg(ax+b)
- Show equation on graph:
VARS → Y-VARS → FUNCTION → Y₁ or ALPHA F4 - Home screen: LinReg(ax+b) L₁, L₂, Y₁
- After regression, residuals auto-store in list RESID.
- Go to top of L₃ → 2nd STAT → #7 RESID → ENTER
- STAT PLOT → Plot1 → ON
- Type: Scatter | XList = L₁ | YList = L₃
- Graph: ZOOM #9 (ZoomStat)
| Function | Description |
|---|---|
| normalcdf(lower, upper, mean, s.d.) | Finds cumulative probability (use 1099 for ∞) |
| normalpdf(x, mean, s.d.) | Graphs the normal curve |
| ShadeNorm(lower, upper, mean, s.d.) | Shows shaded area and % under curve |
| invNorm(%, mean, s.d.) | Finds z-score for given percentile |
- tpdf(x, df): Probability density (graph only)
- tcdf(lower, upper, df): Distribution probability
- invT(left-tail area, df): Finds t-score (not on TI-83)
- binompdf(n, p, r): Probability of exactly r successes
- binomcdf(n, p, r): Probability of ≤ r successes (cumulative)
- geometpdf(p, r): Probability of first success on r-th trial
- geometcdf(p, r): Probability of success within r trials
Formula: \( P(X=r) = (1-p)^{r-1}p \)
- randInt(a,b): Random integer between a & b
- randInt(a,b,n): Generates n integers
- randInt(0,10,100) → L₁: Stores 100 integers in List 1
- randIntNoRep(a,b): No repeats
- rand: Random decimals (0–1)
- rand*12 → L₁: Random decimals scaled 0–12
- randNorm(mean, s.d., n): Generates random normal samples
- Re-seed: Type 5 → rand (sets new seed)
\( (1-p)^{r-1}p \)
p = prob. success
r = r-th trial
Source: TI-84+ Quick Reference Sheet (AP Statistics) — Recreated for students
TI-84+ Quick Reference Sheet — Inferential Testing, CI & ANOVA
Stat vs Data: given actual data choose Data • given summary statistics (mean, s.d.) choose Stats.
1. Z-Test( )
• Tests for one unknown population mean when population s.d. is known.
Use: (1) pop. s.d. is known, (2) sample mean is known, (3) don’t know pop. mean, (4) to test sample mean with some value.
2. T-Test( )
• Test for one unknown pop. mean when pop. s.d. unknown.
Use: (1) sample mean is known, (2) don’t know pop. mean, (3) to test sample mean with some value.
3. 2-Sample ZTest( )
• Test comparing two means when both pop. s.d. are known.
• It is unusual to know both pop. s.d.
• Draw shows z-score and p-value.
4. 2-Sample TTest( )
• Test comparing two means when both pop. s.d. are unknown.
Use: (1) Both sample means and s.d. are known, (2) don’t know pop. means, (3) to test sample mean with some value.
5. 1-Prop ZTest( )
• Tests null hypothesis (no. of successes x, sample size n, alt. hypothesis, display option).
• Computes a test for one proportion of successes.
• Calculates z-score, p-value, and proportion for sample population.
• If given p-hat instead of # of successes x, calculate x by multiplying p-hat × n and rounding to nearest integer.
6. 2-Prop ZTest( )
• Test comparing two proportions of successes.
Use: (1) Working with 2 populations with different n values where both proportions of success are known, (2) to test if there is a statistical difference.
7. Chi-Square Test( )
• Assesses goodness of fit between observed values and those expected.
• Requires observed and expected data in matrix form.
• χ²-Test (matrix observed data, matrix expected data, display option).
8. Chi-Square GOF Test (Goodness of Fit)
• χ² GOF-Test (works with lists).
• Use for simple random sampling, 1 categorical variable, and expected frequency of at least 5.
- Select Data or Stats input:
- Select Data to enter data lists.
- Select Stats to enter statistics (mean, s.d., number).
- Enter values for arguments:
- μ₀ = hypothesized value of population mean being tested
- σ = known pop. s.d. (> 0)
- List = name of list containing data
- Freq = name of list containing frequency (defaults to 1)
- Select alternative hypothesis:
- 1st option for Z-Test
- 2nd for 2-SampTTest
- 3rd for 2-PropZTest
- Select Calculate or Draw:
- Calculate → shows test calculations on home screen (used for Confidence Intervals).
- Draw → shows a graph (auto-adjusted window).
Calculates confidence interval for an unknown mean or proportion of successes.
1. ZInterval( )
• Computes CI for unknown pop. mean when known s.d.
• Use when sample mean and s.d. are known.
• Assume population distribution is normal.
2. TInterval( )
• Computes CI for unknown pop. mean with unknown s.d.
• Use when sample mean and s.d. are known.
• Assume distribution is normal.
3. 2-SampZInt( )
• Computes CI for difference between 2 population means when s.d. are known (rare case).
• Depends on user-specified confidence level.
4. 2-SampTInt( )
• Computes CI for difference between 2 population means when both s.d. are unknown.
• Use when both sample means and s.d. are known.
• Assume both samples are normally distributed.
• Depends on user-specified confidence level.
5. 1-PropZInt( )
• Computes CI for unknown proportion of successes.
• Use when sample size and # of successes are known.
• Depends on user-specified confidence level.
6. 2-PropZInt( )
• Computes CI for difference between proportions of successes in 2 populations.
• Use when 2 samples have different # of successes.
• Depends on user-specified confidence level.
- Computes linear regression on data and performs t-test on slope or correlation coefficient.
- Residuals are created and stored in RESID.
- Used to test the degree of relationship strength.
LinRegTInt:
Computes linear regression T confidence interval for slope coefficient \( b \).
If the confidence interval contains 0 → insufficient evidence that the data exhibits a linear relationship.
χ²pdf(x, df): Yields probability density function value — plots χ² curve with x as the variable.
The mean of a χ² distribution equals the number of degrees of freedom.
χ²cdf(lower bound, upper bound, df): Computes χ² distribution probability over interval.
Finds area under χ² curve between bounds (P[lower < X² < upper]).
One-way analysis of variance:
ANOVA(L₁, L₂, L₃, L₄)
• Compares the means of two to 20 populations.
• Determines if the means differ significantly.
• Computes F-ratio = variance between / variance within groups.
• SS = sum of squares, MS = mean squares.
Source: TI-84+ Quick Reference Sheet (AP Statistics) — Inferential Testing & Confidence Intervals
