# Question

Clinical observations suggest that specifically language-impaired (SLI) children have great difficulty with the proper use of pronouns. This phenomenon was investigated and reported in the Journal of Communication Disorders (Mar. 1995). Thirty children, all from low-income families, participated in the study. Ten were five-year-old SLI children, 10 were younger (three-year-old) normally developing (YND) children, and 10 were older (five-year-old) normally developing (OND) children. The table contains the group, deviation intelligence quotient (DIQ), and percentage of pronoun errors observed for each of the 30 subjects. (The data for these variables, as well as gender, are saved in the SLI file.)

a. Identify the variables in the data set as quantitative or qualitative.

b. Why is it nonsensical to compute numerical descriptive measures for qualitative variables?

c. Compute measures of central tendency for DIQ for the 10 SLI children.

d. Compute measures of central tendency for DIQ for the 10 YND children.

e. Compute measures of central tendency for DIQ for the 10 OND children.

f. Use the results from parts c–e to compare the DIQ central tendencies of the three groups of children. Is it reasonable to use a single number (e.g., mean or median) to describe the center of the DIQ distribution? Or should three “centers” be calculated, one for each of the three groups of children? Explain.

g. Repeat parts c – f for the percentage of pronoun errors.

*h. Plot all the data to investigate a possible trend between DIQ and proper use of pronouns. What do you observe?

*i. Plot the data for the 10 SLI children only. Is there a trend between DIQ and proper use of pronouns?

a. Identify the variables in the data set as quantitative or qualitative.

b. Why is it nonsensical to compute numerical descriptive measures for qualitative variables?

c. Compute measures of central tendency for DIQ for the 10 SLI children.

d. Compute measures of central tendency for DIQ for the 10 YND children.

e. Compute measures of central tendency for DIQ for the 10 OND children.

f. Use the results from parts c–e to compare the DIQ central tendencies of the three groups of children. Is it reasonable to use a single number (e.g., mean or median) to describe the center of the DIQ distribution? Or should three “centers” be calculated, one for each of the three groups of children? Explain.

g. Repeat parts c – f for the percentage of pronoun errors.

*h. Plot all the data to investigate a possible trend between DIQ and proper use of pronouns. What do you observe?

*i. Plot the data for the 10 SLI children only. Is there a trend between DIQ and proper use of pronouns?

## Answer to relevant Questions

According to Benford’s law, certain digits (1, 2, 3, . . . , 9) are more likely to occur as the first significant digit in a randomly selected number than are other digits. For example, the law predicts that the number ...The following Venn diagram describes the sample space of a particular experiment and events A and B : a. Suppose the sample points are equally likely. Find P (A) and P (B). b. Suppose P(1) = P(2) = P(3) = P(4) = P(5) ...Refer to the Environmental Science & Technology (Jan. 2005) study of methyl tert-butyl ether (MTBE) contamination in New Hampshire wells, presented in Exercise 2.21 (p. 37). Data collected for a sample of 223 wells are saved ...The National Institute of Standards and Technology (NIST) mandates that for every 100 items scanned through the electronic checkout scanner at a retail store, no more than 2 should have an inaccurate price. A recent study of ...An experiment results in one of three mutually exclusive events A, B, and C. It is known that P(A) = .30, P(B) = .55, and P(C) = .15, Find each of the following probabilities: a. P(A ∪ B). b. P(A ∩ B)). c. P(A | ...Post your question

0