1. A labor economist wants to know the relationship between education (measured by years of schooling) and annual earnings (measured in $1000). A random sample of 222 workers revealed a correction coefficient of 0.88. Based on the coefficient,
- Earnings would increase by $880 for every year increase in education.
- The slope of the scatter diagram (of education and earnings) equals to 0.88.
- The more education, the higher annual earnings, and the relationship is close.
- All of the above.
2. Among the measures of central tendency (mean, median, mode, quartiles), the most sensitive measure to extreme value(s) is
- mode.
- quartiles.
- mean.
- median.
3. The Pearson's coefficient measures
- the central tendency of a distribution.
- the skewness of a distribution.
- the variability of a distribution.
- none of the above.
4. What is a disadvantage of the range as a measure of dispersion?
- Not in the same units as the original data
- Has no disadvantage
- Based on only two observations
- Can be distorted by a large mean
5. According to Chebyshev's Theorem, at least what percent of the observations lie within plus and minus 1.75 standard deviations of the mean?
- 95%
- 56%
- 67%
- Cannot compute because it depends on the shape of the distribution
6. A sample of the monthly amounts spent for food by families of four receiving food stamps approximates a symmetrical distribution. The sample mean is $150 and the standard deviation is $20. Using the Empirical Rule, about 95 percent of the monthly food expenditures are between what two amounts?
- $205 and $220
- $110 and $190
- $100 and $200
- $85 and $105