15. Simple Statistical Example
Student test scores are scaled to produce grades which have an average of 80 and standard deviation of 15:% cat grades.ss a0:d0 = { "grade", "score", "avg", "stdev"}; mean = avg(b1:b5); c1 = mean; d1 = stdev(b1:b5); a1 = 80+15*(b1-mean)/$d$1; // scaled scores copy a2:a5 a1:a4; b1:b5 = { 57, 67, 92, 87, 76 }; // raw scores eval; print symbols values formulas pointers; % SS --Table grades.ss
mean = avg(B1:B5) = 75.8
| A | B | C | D | |
|---|---|---|---|---|
| 0 | grade | score | avg | stdev |
| 1 | 60.29 | 57.00 | 75.80 | 14.31 |
| 2 | 70.77 | 67.00 | ||
| 3 | 96.98 | 92.00 | ||
| 4 | 91.74 | 87.00 | ||
| 5 | 80.21 | 76.00 | ||
| A | B | C | D | |
| 0 | "grade" | "score" | "avg" | "stdev" |
| 1 | 80+((15*(B1-mean))/$D$1) | 57 | mean | stdev(B1:B5) |
| 2 | 80+((15*(B2-mean))/$D$1) | 67 | ||
| 3 | 80+((15*(B3-mean))/$D$1) | 92 | ||
| 4 | 80+((15*(B4-mean))/$D$1) | 87 | ||
| 5 | 80+((15*(B5-mean))/$D$1) | 76 | ||
| A | B | C | D | |
| 0 | 0x8e4cb88 | 0x8e4cbd8 | 0x8e4cc18 | 0x8e4cc58 |
| 1 | 0x8e4d010 | (nil) | 0x8e4cd90 | 0x8e4ce30 |
| 2 | 0x8e4d010 | (nil) | ||
| 3 | 0x8e4d010 | (nil) | ||
| 4 | 0x8e4d010 | (nil) | ||
| 5 | 0x8e4d010 | (nil) |