chi-square_test
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| chi-square_test [2016/05/15 23:51] – hkimscil | chi-square_test [2025/11/30 23:11] (current) – hkimscil | ||
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| * like to using direct mathematical concepts. There are a lot of repetition | * like to using direct mathematical concepts. There are a lot of repetition | ||
| * here (Dr. Rice once talked about this). | * here (Dr. Rice once talked about this). | ||
| - | * Pictures are taken by your TA at the RUSURE | + | * Pictures are taken by your TA at the RUSURE |
| - | * campaign | + | * which was directed |
| - | * The study is ongoing at the SCILS department. | + | * It is an ongoing |
| Let's start with what we know first. | Let's start with what we know first. | ||
| Line 165: | Line 165: | ||
| | yes | 5 | 32 | 13 | 50 | | | | yes | 5 | 32 | 13 | 50 | | | ||
| | Expected value | (20) | (21) | (9) | 50 | | | | Expected value | (20) | (21) | (9) | 50 | | | ||
| - | | (O-T)2 / T | (-15)< | + | | (O-T)2 / T | (-15)< |
| | no | 35 | 10 | 5 | 50 | | | | no | 35 | 10 | 5 | 50 | | | ||
| | | (20) | (21) | (9) | 50 | | | | | (20) | (21) | (9) | 50 | | | ||
| - | | | (15)< | + | | | (15)< |
| | Total | 40 | 42 | 18 | 100 | 37.58 | | | Total | 40 | 42 | 18 | 100 | 37.58 | | ||
| Chi-square value = 37.58. \\ | Chi-square value = 37.58. \\ | ||
| Line 181: | Line 181: | ||
| 5.991 at 0.05 probability | 5.991 at 0.05 probability | ||
| 9.210 at 0.01 probability | 9.210 at 0.01 probability | ||
| + | < | ||
| + | > qchisq(0.95, | ||
| + | [1] 5.991465 | ||
| + | > qchisq(0.99, | ||
| + | [1] 9.21034 | ||
| + | > | ||
| + | </ | ||
| These critical values do not exceed the chi-square value you obtained from your table -- 37.58. How do you want to relate them together? Think about the expected values -- the ideal types. Suppose you obtained the same values (observed values) as those of expected values, what would be your chi-square value? --Yes, it is going to be zero. Why? If you look at the formula | These critical values do not exceed the chi-square value you obtained from your table -- 37.58. How do you want to relate them together? Think about the expected values -- the ideal types. Suppose you obtained the same values (observed values) as those of expected values, what would be your chi-square value? --Yes, it is going to be zero. Why? If you look at the formula | ||
| Line 251: | Line 258: | ||
| 5.991 (0.05 probability) | 5.991 (0.05 probability) | ||
| 9.210 (0.01 probability) | 9.210 (0.01 probability) | ||
| + | |||
| + | OR | ||
| + | < | ||
| + | > pchisq(2.73, | ||
| + | [1] 0.7446193 | ||
| + | </ | ||
| Now the rest of what you need to do is to compare the numbers (chi-square value and the critical values). | Now the rest of what you need to do is to compare the numbers (chi-square value and the critical values). | ||
chi-square_test.1463356315.txt.gz · Last modified: by hkimscil