Financial Calculator User Guide
STAT · Statistics
Choose an instruction to see the matching keys and values. Practice separately in the real calculator.
Open financial calculator ↗Worked examples
Know the mode controls
DATA stores observations; EXE advances through X, Y and optional FREQ. Choose RESULTS, select an output and SOLVE. FREQ counts repetitions; it must be a positive integer. LOG and POWER require positive X; EXP, A·Bˣ and POWER require positive Y; INV excludes X = 0.
Review these controls before choosing a case. Keystroke steps show menus opening, selection and closure.
- Type selector
- Open the upper 1-VAR selector and choose a model. Enter opens, ↑↓ moves, Enter confirms and Escape cancels. Options: 1-VAR, LIN, QUAD, LOG, EXP, A·Bˣ, POWER and INV.
- DATA · Observations
- Choose DATA, select each X/Y cell, enter a value and EXE. A blank tail is added automatically. Select stored cells to edit; ⌫ beside DATA deletes the current observation. MENU → Clear mode clears the data.
- RESULTS · Results
- RESULTS retains DATA. Select a result row and SOLVE. Changing between DATA/RESULTS preserves data and computed results; editing data or Settings invalidates results and requires solving again.
- FREQ · Frequency
- MENU → Settings → FREQ: OK toggles On/Off; ← returns to DATA. On requires a positive integer frequency per observation. Off keeps stored frequencies but treats each observation once.
- 1-VAR · One variable
- Solve mean x̄, sample deviation sx, count n, sum Σx, sum of squares Σx², population deviation σx and minX/maxX. With FREQ on, n totals frequencies; sx needs at least two weighted observations.
- Regression · Models
- LIN linear, QUAD quadratic, LOG logarithmic, EXP exponential, A·Bˣ exponential, POWER power and INV inverse. RESULTS exposes model-specific A/B/C/r, x/y prediction inputs and ŷ/x̂/x̂2. Complete model workflows follow below.
- After switching type
- Stored X/Y and FREQ data remain, with inapplicable columns hidden. Derived results clear. Check complete data and domains before solving the new model. Clear mode restores 1-VAR and FREQ Off.
x̄ · Open lesson
x̄ · Arithmetic Mean of X — Sum of X divided by the observation count. Repeated observations are included when FREQ is On.
1. Organize the inputs
Mean and sample deviation of five observations
Use 1-VAR with FREQ off. For X=1,2,3,4,5, find mean x̄ and sample deviation sx.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| X 2 | 2 | EXE |
| X 3 | 3 | EXE |
| X 4 | 4 | EXE |
| X 5 | 5 | EXE |
| x̄ | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
3. Show answer and interpretation
data units
Mean is 3 and sample deviation approximately 1.5811, dividing by n−1. It differs from population σx. Y and frequency are unused here.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗sx · Open lesson
sx · Sample Standard Deviation — Uses n − 1 in the variance denominator. At least two observations, including frequencies, are required.
1. Organize the inputs
Mean and sample deviation of five observations
Use 1-VAR with FREQ off. For X=1,2,3,4,5, find mean x̄ and sample deviation sx.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| X 2 | 2 | EXE |
| X 3 | 3 | EXE |
| X 4 | 4 | EXE |
| X 5 | 5 | EXE |
| sx | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
3. Show answer and interpretation
data units
Mean is 3 and sample deviation approximately 1.5811, dividing by n−1. It differs from population σx. Y and frequency are unused here.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗n · Open lesson
n · Number of Observations — The number of observations, including repetitions when FREQ is enabled.
1. Organize the inputs
Number of Observations — manual workflow
Calculate a statistic or prediction from observations. Given (1) · (2) · (3) · (4) · (5), use the settings below to find n manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| X 2 | 2 | EXE |
| X 3 | 3 | EXE |
| X 4 | 4 | EXE |
| X 5 | 5 | EXE |
| n | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
3. Show answer and interpretation
observations
Number of Observations: 5. The number of observations, including repetitions when FREQ is enabled.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗Σx · Open lesson
Σx · Sum of X — The sum of observed X values, weighted by FREQ when enabled.
1. Organize the inputs
Sum of X — manual workflow
Calculate a statistic or prediction from observations. Given (1) · (2) · (3) · (4) · (5), use the settings below to find Σx manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| X 2 | 2 | EXE |
| X 3 | 3 | EXE |
| X 4 | 4 | EXE |
| X 5 | 5 | EXE |
| Σx | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
3. Show answer and interpretation
data units
Sum of X: 15. The sum of observed X values, weighted by FREQ when enabled.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗Σx² · Open lesson
Σx² · Sum of Squared X — Square each observed X, then add the squares, including frequencies. This differs from squaring the sum of X.
1. Organize the inputs
Sum of Squared X — manual workflow
Calculate a statistic or prediction from observations. Given (1) · (2) · (3) · (4) · (5), use the settings below to find Σx² manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| X 2 | 2 | EXE |
| X 3 | 3 | EXE |
| X 4 | 4 | EXE |
| X 5 | 5 | EXE |
| Σx² | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
3. Show answer and interpretation
data units
Sum of Squared X: 55. Square each observed X, then add the squares, including frequencies. This differs from squaring the sum of X.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗σx · Open lesson
σx · Population Standard Deviation — Measures spread around the mean using n in the variance denominator. A constant dataset has zero spread.
1. Organize the inputs
Population Standard Deviation — manual workflow
Calculate a statistic or prediction from observations. Given (1) · (2) · (3) · (4) · (5), use the settings below to find σx manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| X 2 | 2 | EXE |
| X 3 | 3 | EXE |
| X 4 | 4 | EXE |
| X 5 | 5 | EXE |
| σx | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
3. Show answer and interpretation
data units
Population Standard Deviation: 1.4142135623730951. Measures spread around the mean using n in the variance denominator. A constant dataset has zero spread.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗minX · Open lesson
minX · Minimum X — The smallest entered X value; frequencies do not change its value.
1. Organize the inputs
Minimum X — manual workflow
Calculate a statistic or prediction from observations. Given (1) · (2) · (3) · (4) · (5), use the settings below to find minX manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| X 2 | 2 | EXE |
| X 3 | 3 | EXE |
| X 4 | 4 | EXE |
| X 5 | 5 | EXE |
| minX | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
3. Show answer and interpretation
data units
Minimum X: 1. The smallest entered X value; frequencies do not change its value.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗maxX · Open lesson
maxX · Maximum X — The largest entered X value; frequencies do not change its value.
1. Organize the inputs
Maximum X — manual workflow
Calculate a statistic or prediction from observations. Given (1) · (2) · (3) · (4) · (5), use the settings below to find maxX manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| X 2 | 2 | EXE |
| X 3 | 3 | EXE |
| X 4 | 4 | EXE |
| X 5 | 5 | EXE |
| maxX | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
3. Show answer and interpretation
data units
Maximum X: 5. The largest entered X value; frequencies do not change its value.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗FREQ · Open lesson
FREQ · Arithmetic Mean of X · Frequency and data editing — Sum of X divided by the observation count. Repeated observations are included when FREQ is On.
1. Organize the inputs
Arithmetic Mean of X · Frequency and data editing — manual workflow
Calculate a statistic or prediction from observations. Given (1, FREQ=2) · (3, FREQ=1) · (5, FREQ=1), use the settings below to find x̄ manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| Freq 1 | 2 | EXE |
| X 2 | 3 | EXE |
| Freq 2 | 1 | EXE |
| X 3 | 5 | EXE |
| Freq 3 | 1 | EXE |
| x̄ | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
Steps 13–18
Steps 19–22
3. Show answer and interpretation
data units
Arithmetic Mean of X · Frequency and data editing: 2.5. Sum of X divided by the observation count. Repeated observations are included when FREQ is On.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗LIN · Open lesson
LIN · Linear regression — Model y=A+B*x. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
1. Organize the inputs
Linear regression — manual workflow
Calculate a statistic or prediction from observations. Given (1, 3) · (2, 5) · (3, 7) · (4, 9), use the settings below to find ŷ manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| Y 1 | 3 | EXE |
| X 2 | 2 | EXE |
| Y 2 | 5 | EXE |
| X 3 | 3 | EXE |
| Y 3 | 7 | EXE |
| X 4 | 4 | EXE |
| Y 4 | 9 | EXE |
| x | 2.5 | EXE |
| y | 6 | EXE |
| ŷ | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
Steps 13–18
Steps 19–22
3. Show answer and interpretation
Y units
Linear regression: 6. Model y=A+B*x. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
- QUAD may have two inverse roots. r measures linear association in transformed coordinates, not causation or future performance.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗QUAD · Open lesson
QUAD · Quadratic regression — Model y=A+B*x+C*x^2. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
1. Organize the inputs
Quadratic regression — manual workflow
Calculate a statistic or prediction from observations. Given (1, 1) · (2, 4) · (3, 9) · (4, 16), use the settings below to find ŷ manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| Y 1 | 1 | EXE |
| X 2 | 2 | EXE |
| Y 2 | 4 | EXE |
| X 3 | 3 | EXE |
| Y 3 | 9 | EXE |
| X 4 | 4 | EXE |
| Y 4 | 16 | EXE |
| x | 2.5 | EXE |
| y | 4 | EXE |
| ŷ | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
Steps 13–18
Steps 19–23
3. Show answer and interpretation
Y units
Quadratic regression: 6.25. Model y=A+B*x+C*x^2. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
- QUAD may have two inverse roots. r measures linear association in transformed coordinates, not causation or future performance.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗LOG · Open lesson
LOG · Logarithmic regression — Model y=A+B*ln(x). Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
1. Organize the inputs
Logarithmic regression — manual workflow
Calculate a statistic or prediction from observations. Given (1, 1) · (2, 2.386294361119891) · (3, 3.197224577336219) · (4, 3.772588722239781), use the settings below to find ŷ manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| Y 1 | 1 | EXE |
| X 2 | 2 | EXE |
| Y 2 | 2.386294361 | EXE |
| X 3 | 3 | EXE |
| Y 3 | 3.197224577 | EXE |
| X 4 | 4 | EXE |
| Y 4 | 3.772588722 | EXE |
| x | 2.5 | EXE |
| y | 2.832581464 | EXE |
| ŷ | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
Steps 13–18
Steps 19–22
3. Show answer and interpretation
Y units
Logarithmic regression: 2.83258146374831. Model y=A+B*ln(x). Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
- QUAD may have two inverse roots. r measures linear association in transformed coordinates, not causation or future performance.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗EXP · Open lesson
EXP · Exponential regression — Model y=A*exp(B*x). Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
1. Organize the inputs
Exponential regression — manual workflow
Calculate a statistic or prediction from observations. Given (1, 3.2974425414002564) · (2, 5.43656365691809) · (3, 8.963378140676129) · (4, 14.7781121978613), use the settings below to find ŷ manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| Y 1 | 3.297442541 | EXE |
| X 2 | 2 | EXE |
| Y 2 | 5.436563657 | EXE |
| X 3 | 3 | EXE |
| Y 3 | 8.963378141 | EXE |
| X 4 | 4 | EXE |
| Y 4 | 14.778112198 | EXE |
| x | 2.5 | EXE |
| y | 6.980685915 | EXE |
| ŷ | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
Steps 13–18
Steps 19–22
3. Show answer and interpretation
Y units
Exponential regression: 6.980685914923683. Model y=A*exp(B*x). Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
- QUAD may have two inverse roots. r measures linear association in transformed coordinates, not causation or future performance.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗ABX · Open lesson
ABX · A·Bˣ regression — Model y=A*B^x. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
1. Organize the inputs
A·Bˣ regression — manual workflow
Calculate a statistic or prediction from observations. Given (1, 3) · (2, 4.5) · (3, 6.75) · (4, 10.125), use the settings below to find ŷ manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| Y 1 | 3 | EXE |
| X 2 | 2 | EXE |
| Y 2 | 4.5 | EXE |
| X 3 | 3 | EXE |
| Y 3 | 6.75 | EXE |
| X 4 | 4 | EXE |
| Y 4 | 10.125 | EXE |
| x | 2.5 | EXE |
| y | 5.511351921 | EXE |
| ŷ | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
Steps 13–18
Steps 19–22
3. Show answer and interpretation
Y units
A·Bˣ regression: 5.5113519212621505. Model y=A*B^x. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
- QUAD may have two inverse roots. r measures linear association in transformed coordinates, not causation or future performance.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗POWER · Open lesson
POWER · Power regression — Model y=A*x^B. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
1. Organize the inputs
Power regression — manual workflow
Calculate a statistic or prediction from observations. Given (1, 2) · (2, 5.656854249492381) · (3, 10.392304845413264) · (4, 16), use the settings below to find ŷ manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| Y 1 | 2 | EXE |
| X 2 | 2 | EXE |
| Y 2 | 5.656854249 | EXE |
| X 3 | 3 | EXE |
| Y 3 | 10.392304845 | EXE |
| X 4 | 4 | EXE |
| Y 4 | 16 | EXE |
| x | 2.5 | EXE |
| y | 7.90569415 | EXE |
| ŷ | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
Steps 13–18
Steps 19–22
3. Show answer and interpretation
Y units
Power regression: 7.905694150420948. Model y=A*x^B. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
- QUAD may have two inverse roots. r measures linear association in transformed coordinates, not causation or future performance.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗INV · Open lesson
INV · Inverse regression — Model y=A+B/x. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
1. Organize the inputs
Inverse regression — manual workflow
Calculate a statistic or prediction from observations. Given (1, 3) · (2, 2) · (3, 1.6666666666666665) · (4, 1.5), use the settings below to find ŷ manually.
| Variable | Input | Action |
|---|---|---|
| X 1 | 1 | EXE |
| Y 1 | 3 | EXE |
| X 2 | 2 | EXE |
| Y 2 | 2 | EXE |
| X 3 | 3 | EXE |
| Y 3 | 1.666666667 | EXE |
| X 4 | 4 | EXE |
| Y 4 | 1.5 | EXE |
| x | 2.5 | EXE |
| y | 1.8 | EXE |
| ŷ | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–6
Steps 7–12
Steps 13–18
Steps 19–22
3. Show answer and interpretation
Y units
Inverse regression: 1.8. Model y=A+B/x. Enter paired X/Y observations manually, solve coefficients and make forward and inverse predictions.
4. Avoid these mistakes
- Store complete X/Y observations and positive-integer FREQ when enabled; the blank tail is excluded. sx needs two observations; LOG/POWER require X>0, EXP/ABX/POWER require Y>0 and INV requires X≠0. Re-solve after editing or deleting DATA.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
- QUAD may have two inverse roots. r measures linear association in transformed coordinates, not causation or future performance.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗Supported results and operating manual
Targets across the lessons: x̄ · sx · n · Σx · Σx² · σx · minX · maxX · A · B · r · ŷ · x̂ · C · x̂2
STAT · Operating manual
- Choose 1-VAR or a regression model, enter X in DATA (and Y for regression).
- With FREQ enabled, enter positive integer frequencies.
- Switch to results, select a statistic and SOLVE.
- Sample deviation needs at least two observations; LOG/POWER require positive X, EXP/POWER positive Y, and INV nonzero X.
Keys and settings
Keys and workflow
- ↑↓ selects the active row. The highlighted row is the variable you are editing.
- Enter a number or expression (500*6 or 10000*(1.05)^10), then EXE to evaluate, store and advance. Dates use date input instead of expressions.
- SOLVE calculates the selected unknown/output from the other known values. MATH uses EXE only.
- CLR clears the draft while editing; otherwise it clears only the selected stored variable. Backspace recalls a stored value and deletes its last character, then EXE stores the change. Escape cancels a draft and restores the original value. After EXE advances, select the field you want to change. Clearing a stored input invalidates dependent results. Selecting a read-only result or history row leaves it untouched; settings and MATH history are preserved. MENU offers current-mode clear and calculator reset.
MENU → Fill Example provides working inputs for the current mode. N/A or an error means the inputs/settings do not support a valid result; check the highlighted field and domain restrictions.
Need help with signs or EXE/SOLVE? Read FAQ