Homework SourseA geologist collects handspecimen sized pieces of limestone
A geologist collects hand-specimen sized pieces of limestone from a particular
area. A qualitative assessment of both texture and color is made with the
following results. Is there evidence of association between color and texture for
these limestones? Explain your answer.
| Color | |||
| TEXTURE | LIGHT | MEDIUM | DARK |
| fine | 4 | 20 | 8 |
| medium | 5 | 23 | 12 |
| course | 21 | 23 | 4 |
Solution
H0: There is no association between colour and quality
Ha: There is association.
The chi-square statistic is 17.7273. The P-Value is 0.001395. The result is significant at p < 0.05.
As p value is very small reject H0.
| Results | ||||||
| Light | Medium | Dark | Row Totals | |||
| Fine | 4 (8.00) [2.00] | 20 (17.60) [0.33] | 8 (6.40) [0.40] | 32 | ||
| Medium | 5 (10.00) [2.50] | 23 (22.00) [0.05] | 12 (8.00) [2.00] | 40 | ||
| Coarse | 21 (12.00) [6.75] | 23 (26.40) [0.44] | 4 (9.60) [3.27] | 48 | ||
| Column Totals | 30 | 66 | 24 | 120 (Grand Total) |
