The following data is for worker output in a plant, for different 
hours of the day, with a numerical measurement on their production: 
hour -    1   2   3   4   5   6   7
output - .5 2.6 3.6 4.5 4.9 5.4 5.7 

Find the natural logarithmic regression model for this data

On your T-83 or TI-83+ or TI-84 calculator,

press 2nd 
+ 
4 
ENTER
STAT
1
(under L1 type in  1   2   3   4   5   6   7)
(under L2 Type in .5 2.6 3.6 4.5 4.9 5.4 5.7)
STAT
(Press Right arrow to CALC)
9
ENTER

At this point you will see
y=a+blnx
a=.6298052609
b=2.673423984
r²=.9961628996
r=.9980796059

Your regression model is y = a + b·ln(x)
where a and b are the values above.

To see the scatter plot of your points:
2nd
Y=
ENTER
ENTER
(Press Down arrow)
ENTER
WINDOW
(Set Xmin=0, Xmax=8, Xscl=1, Ymin=0, Ymax=6, Yscl=1, Xres=1)
GRAPH

To see the regression curve
Y=
CLEAR
VARS
5
(Press Right arrow key twice to EQ)
ENTER
GRAPH
 
Edwin