# Question

The following quote is from the paper “Evaluation of the Accuracy of Different Methods Used to Estimate Weights in the Pediatric Population” (Pediatrics [2009]: e1045–e1051): As expected, the model demonstrated that weight increased with age, but visual inspection of an age versus weight plot demonstrated a nonlinear relationship unless infants and children were analyzed separately. The linear coefficient for age as a predictor of weight was 6.93 in infants and 3.1 to 3.48 in children. This quote suggests that when a scatterplot of weight versus age was constructed for all 1011 children in the study described in the paper, the relationship between y = weight and x = age was not linear. When the 1011 children were separated into two groups—infants (age birth to 1 year) and children (age 1 to 10 years)—and separate scatterplots were constructed, the relationship between weight and age appeared linear in each scatterplot. The slopes reported in the given quote (referred to as “the linear coefficient”) are expressed in kg/year. Briefly explain why the relationship between weight and age in the scatterplot for the combined group would appear nonlinear.

## Answer to relevant Questions

The accompanying data represent x = amount of catalyst added to accelerate a chemical reaction and y 5 resulting reaction time: a. Calculate r. Does the value of r suggest a strong linear relationship? b. Construct a ...Percentages of public school students in fourth grade in 1996 and in eighth grade in 2000 who were at or above the proficient level in mathematics were given in the article “Mixed Progress in Math” (USA Today, August 3, ...An accurate assessment of oxygen consumption provides important information for determining energy expenditure requirements for physically demanding tasks. The paper “Oxygen Consumption During Fire Suppression: Error of ...USA Today (March 15, 2001) introduced a measure of racial and ethnic diversity called the Diversity Index. The Diversity Index is supposed to approximate the probability that two randomly selected individuals are racially or ...On April 1, 2000, the Bureau of the Census in the United States attempted to count every U.S. resident. Suppose that the counts in the table on the next page are obtained for four counties in one region. a. If one person is ...Post your question

0