How is proximity defined in pMLU?

How is proximity defined in pMLU?

• A. Proximity equals number of words known
• B. Proximity equals child pMLU divided by adult pMLU times 100
• C. Proximity equals age at first word
• D. Proximity equals number of consonants in vocabulary

Answer: (B)

Proximity in pMLU measures how close a child’s syntactic development is to an adult’s, expressed as a percentage. It does this by comparing the child’s mean length of utterance (MLU) to the adult’s MLU. Practically, you calculate proximity by taking the child’s MLU, dividing it by the adult’s MLU, and multiplying by 100. If you use the pMLU values themselves, it’s the same idea: the ratio of the child’s pMLU to the adult’s pMLU, times 100, gives the percentage of adult language the child has reached. For example, a child with MLU 2.0 and adult MLU 4.0 would have a proximity of 50%, meaning the child’s syntactic development is halfway to adult level.

Proximity in pMLU measures how close a child’s syntactic development is to an adult’s, expressed as a percentage. It does this by comparing the child’s mean length of utterance (MLU) to the adult’s MLU. Practically, you calculate proximity by taking the child’s MLU, dividing it by the adult’s MLU, and multiplying by 100. If you use the pMLU values themselves, it’s the same idea: the ratio of the child’s pMLU to the adult’s pMLU, times 100, gives the percentage of adult language the child has reached. For example, a child with MLU 2.0 and adult MLU 4.0 would have a proximity of 50%, meaning the child’s syntactic development is halfway to adult level.