With the Texas Instruments TI-36, as with many scientific calculators, you can calculate the most commonly-used descriptive statistics for one variable (mean, standard deviation, sum of values, sum of the values-squared) and for regression/correlation between two variables (regression coefficient and intercept, correlation coefficient). Data entry is more critical (and somewhat more complicated) than with the graphing calculators because the values are not saved in a list, so you cannot review & check the data entry.
The reference to SIGMA+ (SIGMA-) and SIGMAx (etc.) indicate the keys labeled with the Greek capital letter Sigma, representing summation, with the + or - or x (etc.). The reference to x^2 indicates the "x-squared" key, SQRTx means the "square root of x" key. Keys are indicated by the White (main) label - the corresponding colored (2nd or 3rd function) label is indicated in brackets ( [ ] ).
You have to enter the data depending on the calculation to be done - must be very careful to enter values correctly.
There are three situations in which you enter data - one variable (actual data), one variable (with frequencies - grouped or ungrouped), two variable. Always clear old data before entering new data, or your results will be messed up:
Make sure everything is cleared ( press AC/ON)
Press 3rd x><y [STAT1] (to get into "one-variable stats"
mode-"STAT" keyword appears at bottom of window-still use mostly
White key labels for data entry) enter first number & press SIGMA+
(display shows your number, until you press SIGMA+, it then shows 1 to indicate
1 value has been entered), enter 2nd number (display shows number) then
press SIGMA+ (display shows 2 to indicate 2 values have been entered) -
etc. until all values have been entered (display shows how many values have
been entered)
If you know you have mis-entered a value (there is no way to check
by looking at the calculator), you can remove it: Enter the value (that
you shouldn't have entered -it will show on display) and press 2nd SIGMA+[SIGMA-]
(count of values remaining - one less than before - shows in display).
Clear (press AC/ON) Press 3rd x><y[STAT1]
) enter first value (display shows value), press 2nd-1/x[FRQ] enter frequency
press SIGMA+ (display shows frequency) , enter second value (display shows
value), press 2nd-1/x[FRQ], enter 2d frequency press SIGMA+ (display shows
cumulative frequency) etc.]
Make sure everything is cleared (press AC/ON a couple of times). Press 3rd- SIGMA+[STAT2] enter 1st x-value (it shows on display) press x><y (last y-value shows on display) enter 1st y value(it shows on display), press SIGMA+ (1 appears on display - indicating 1 pair entered) enter 2nd x-value (it appears on display), press x<>y (previous y-value appears on display), enter 2nd y-value (it appears), press SIGMA+ (2 appears on display) etc. That is - press x><y after each x-value, press SIGMA+ after each y-value.
Press appropriate key for the result you want -
they are labeled in orange and require use of the 2nd function key
Mean : 2nd-x^2 , Sample standard deviation Sx: 2nd-SQRT(x) (sig(n-1))
, sum of x's: 2nd-STO [ SIGMAx], sum of x-squareds (note this
is not "sum of squares"): 2nd-7 [ Sum x^2 ], Count of values (n) :
2nd-EE[n]
You can keep selecting results until you enter other values into the calculator
(so you can get mean, then standard deviation, etc.)
Press appropriate key for the result you want - most are labeled in orange
and requre use of the 2nd function key (correlation uses 3rd)
Slope of regression line:
2nd-5 [SLP], intercept of regression line: 2nd-4[ITC], correlation
coefficient r: 3rd-4[COR], sum of x's: 2nd-STO [Sumx], sum
of y's: 2nd-8 [Sumy], Sum of x-squareds: 2nd-7 [Sumx^2], sum
of y-squareds: 2nd-9[Sumy^2], sum of xy's: 2nd- - [Sumxy] .
You can keep selecting results (so you can get coefficient, then intercept,
r, etc.) until you enter other values into the calculator .
Errors or questions? Please let me know: cpeltier@saintmarys.edu
Last update 7/20/98