Algebra 1 – Unit #3 - Statistics Lie… Find out How Name:
Unit Assessment Date:
The scatterplot below shows the finishing times for the Olympic gold medalist in the men’s 100–meter dash for previous Olympic Games.
The line of best fit is and has an R-value of .8166. Use this model to answer questions 1-4.
1. What is the best explanation for why this is a good linear model?
a. As the years increase, the gold medal time is going down.
b. The cluster from 1984 to 2012 fits a linear model.
c. The R-value suggests a strong correlation.
d. The scatterplot is an accurate fit.
2. Given that the summer Olympic Games takes place every four years, how should we expect the gold medalist’s finishing time to change from one Olympic Games to the next?
a. The time will be expected to increase by 0.01 seconds in the next Olympic Games.
b. The time will be expected to increase by 10.9 seconds in the next Olympic Games.
c. The time will be expected to decrease by 0.01 seconds in the next Olympic Games.
d. The time will be expected to decrease by 0.04 seconds in the next Olympic Games.
3. What is the y-intercept of the model? What does it mean in context of the problem?
a. There is no y-intercept for the model because times aren’t available for year 0.
b. The y-intercept of the model is 10.9. This means that the first Olympic Games had a winning time of 10.9
c. The y-intercept of the model is 10.9. This means that the 1900 Olympic Games had a winning time of 10.9.
d. The y-intercept of the model is 0.01. This means that the graph starts at 0.01.
4. Note that the gold medalist finishing time for the 1940 Olympic Games is not included in the scatterplot. Use the model to estimate the gold medalist’s finishing time. Provide evidence to how that conclusion is reached.
A movie theater recorded the number of tickets sold for two movies each day during one week. Box plots of the data are shown below.
Based on the box plots, determine whether each of the following statements is True, False, or Cannot be Determined from the information given in the box plot.
True / False / Cannot Be Determined5. The mean number of tickets sold for Movie X is greater than the mean number sold for Movie Y. /
6. The median number of tickets sold for Movie X is greater than the median number of tickets sold for Movie Y.
7. What does the y-intercept of a linear model represent?
a. The value of the independent variable when the dependent variable equals zero.
b. The value of the dependent variable when the independent variable equals zero.
c. The value of the independent variable when the dependent variable equals its maximum value.
d. The value of the independent variable when the dependent variable equals its minimum value.
Ages / Frequency22 / 3
23 / 2
27 / 2
29 / 1
30 / 2
8. The frequency table to the right shows the ages of the first ten people in line at the movie theater. Make a line plot that shows the same data as the frequency table.
a. / / c. /b. / / d. /
9. What type of relationship does the scatterplot to the right show?
a. Positive Correlation
b. Negative Correlation
c. No Correlation
10. What type of relationship does the scatterplot to the right show?
a. Positive Correlation
b. Negative Correlation
c. No Correlation
11. The scatter plot shows the number of mistakes a piano student makes during a recital versus the amount of time the student practiced for the recital. How many mistakes do you expect a student to make at the recital after 16 hours of practicing?
a. 27 mistakes
b. 32 mistakes
c. 23 mistakes
d. 39 mistakes
12. At a city council meeting, one resident expressed concern that more coffee shops in a community increase property crimes in the city. Before collecting data, do you expect the correlation to be strong or weak? Will this correlation reflect a causal relationship?
a. There will be a causal correlation and it will be strong.
b. There will be a causal correlation and it will be weak.
c. There will not be a causal relationship; however, the correlation will be strong.
d. There will not be a causal relationship and the correlation will be weak.
13. Describe the correlation and causation relationship between the average daily winter temperature and your heating bill.
a. There is a causal correlation and it is positive. The higher the average daily winter temperature, the higher your heating bill.
b. There is a causal correlation and it is negative. The higher the average daily winter temperature, the lower your heating bill.
c. There is correlation and it is positive, however, it is not causal. The higher the average daily winter temperature, the higher your heating bill.
d. There is a correlation and it is negative, however, it is not causal. The higher the average daily winter temperature, the lower your heating bill.
14. Describe the shape of the histogram of the results of a mathematics test.
a. Symmetric
b. Negative Skewed (Left)
c. Uniform
d. Positive Skewed (Right)
15. Which box-and-whisker plot represents the data set?
{21, 27, 22, 22, 25, 14, 16, 10}
a. /b. /
c. /
d. /
16. The data below shows the average number of text messages a group of students send per day. Which histogram represents the data?
{20, 5, 8, 22, 10, 1, 7, 15, 16, 12, 15, 6, 13, 8}
a. / / c. /b. / / d. /
The dot plots below compare the number of minutes 30 flights made by two airlines arrived before or after their scheduled arrival times. Dots to the left of zero represent flights that were early and dots to the right of zero represent flights that were late.
For each of the following statistics, determine whether the value of the statistic is greater for Airline P, equal for both airlines, or greater for Airline Q.
Greater for Airline P / Equal for Both Airlines / Greater for Airline Q17. The median /
18. The standard deviation
19. The two box-and-whisker plots below show the times in seconds for two teams in a 100 meter dash. What do the interquartile ranges tell you about the two teams?
a. / Team A has more consistent timesb. / Team B has more consistent times
c. / Overall team A is faster than team B
d. / Overall team B is faster than team A
20. For the two box-and-whisker plots from the previous problem (#19), describe the outliers.
a. The minimum of Team A and the maximum of Team B are outliers
b. There are no outliers in the data sets
c. The minimum of Team A and the maximum of Team A are outliers
d. The maximum of Team A and the maximum of Team B are outliers
21. Which measure of center is always affected by an outlier?
a. Median
b. Standard Deviation
c. Mean
d. Inner Quartile Range