# Glossary M

## Glossary M

**Mean** is defined as the measure that represents an arithmetic average of a set of numbers. Mean is derived by dividing the sum of a group of numerical items by the total number of items in that group. For example, mean family income is obtained by dividing the total of all income reported by people 15 years and over in families by the total number of families. Moreover, Mean is a measure of central tendency obtained by summing the individual scores and dividing the sum by the number of scores.

**Mean effect size**used in meta-analysis , a statistic that is the average of the effect sizes for all studies included in the analysis.

**Mean length of utterance (MLU)** refers to a measure of language development defined by the average number of meaningful language units (root words and endings) a child uses at any one time. ** Mean length of utterance (MLU)**, moreover, is defined as the common measure of grammatical development. It is the average length of the utterances in a sample of spontaneous speech , often counted in terms of the number of morphemes.

**Mean treatment effect size ** is defined as a statistic for representing the size of the effect of an experimental manipulation on behavior it is calculated by subtracting the mean of the control group from the mean of the treatment group and dividing by the standard deviation of the control group.

**Mean-world belief**refers to a belief, fostered by televised violence, that the world is a more dangerous and frightening place than is actually the case.

**Meaning reconstruction** refer to efforts to make sense of loss by finding or creating new meaning in the death of the loved one and in the new life of the bereaved person. Neimeyer has written about the importance for bereaved persons of engaging in a process of reconstruring meaning in their lives and has asserted that "meaning reconstruction" in response to loss is the central process in grieving.

**Means –ends analysis**refers to a problem-solving strategy in which the solver compares the goal to the current state, then chooses a step to reduce maximally the difference between them.

**Measurement**refers to the process of assigning numbers or categories to performance according to rules and standards, example, scoring a test ; the systematic assignment of numbers or names to objects or attributes of objects