| Effect | Condition | Means | Standard Error | |
| Grammaticality | Grammatical | 7.012 | 0.034 | |
| Ungrammatical | 7.030 | 0.035 | ||
| Morpheme | Null (dog) | 7.003 | 0.034 | |
| Plural (dogs) | 7.039 | 0.037 | ||
| Interaction | Grammatical Null (this dog) | 6.989 | 0.033 | |
| Ungrammaical Null (these *dog) | 7.017 | 0.036 | ||
| Grammatical Plural (these dogs) | 7.035 | 0.039 | ||
| Ungrammatical Plural (this *dogs) | 7.043 | 0.037 | ||