# Introduction to Computers

### Laboratory Assignment # 5

1. Assume your friend in the physics lab has measured four sets of X-Y data listed in Table 1.3 and has asked you, as an Excel spreadsheet expert, to do a statistical analysis of the data. Key in the four sets of data in columns B Æ L and, below the data, compute the following statistical properties of each of the 8 columns:

```Quantity                           Excel Function Call
Number of data items                =count(B4:B14)
Largest value in list               =max(B4:B14)
Smallest value in list              =min(B4:B14)
Median (middle value)               =median(B4:B14)
(§) Average of items in column      =average(B4:B14)
(§) Standard deviation(§)           =stdev(B4:B14)
```

Based on the (§) statistical tests, how would you advise your physics friend as to whether these four sets of X-Y measurements are or are not drawn from the same parent population (i.e., are they four different measurements of the "same thing" or measurements of four different things based on these statistics)?

2. Next, do a graphical analysis of the data by plotting Y vs. X for all four sets of data.  Based on similarities or differences in the shapes of these curves, re-evaluate your advice from Problem 1.  That is, do the shapes of the curves suggest that all four curves measure the "same thing" or different things?

### Table 1.3

Four Sets of  X-Y Measurements
 X1 Y1 X2 Y2 X3 Y3 X4 Y4 10.00 8.04 10.00 9.14 10.00 7.46 8.00 6.58 8.00 6.95 8.00 8.14 8.00 6.77 8.00 5.76 13.00 7.58 13.00 8.74 13.00 12.74 8.00 7.71 9.00 8.81 9.00 8.77 9.00 7.11 8.00 8.84 11.00 8.33 11.00 9.26 11.00 7.81 8.00 8.47 14.00 9.96 14.00 8.10 14.00 8.84 8.00 7.04 6.00 7.24 6.00 6.13 6.00 6.08 8.00 5.25 4.00 4.26 4.00 3.10 4.00 5.39 19.00 12.50 12.00 10.84 12.00 9.13 12.00 8.15 8.00 5.56 7.00 4.82 7.00 7.26 7.00 6.42 8.00 7.91 5.00 5.68 5.00 4.74 5.00 5.73 8.00 6.89