Refer to Exercise 14.139. The AGI categories for another study were $100,000 to $199,999 $200,000 to $249,999 $250,000 to $499,999 $500,000 to $1,000,000 The proportion of charitable giving to AGI was recorded. a. Is there sufficient evidence to conclude that there are differences between the four AGI categories? b. If differences exist use Tukey’s method to determine which groups differ.
Exercise 14.139
The National Center for Charitable Statistics estimates that individual giving in the United States in 2014 was $258.51 billion. A study to determine who gave and how much they gave was undertaken. A random sample of individuals who gave to charities was drawn. For each respondent, the study recorded the total adjusted gross income (AGI) category and the charitable giving as a percentage of AGI. The AGI categories are listed next. In this study, only individuals whose AGI was between $45,000 and $100,000 were included. $45,000 to $49,999 $50,000 to $54,999 $55,000 to $59,999 $60,000 to $74,999 $75,000 to $100,000 a. Is there sufficient evidence to conclude that there are differences between the five AGI categories? b. If differences exist use Tukey’s method to determine which groups differ.