#### Test One: MS 150 Statistics Summer 2001

1. Four boxes of dried sakau are being weighed for shipment to Guam, they have the following weights:
60 pounds, 64 pounds, 67 pounds, 65 pounds
This data is an example of what level of measurement?

2. The TOEFL scores for OIHS are given by the following data set:

483, 487, 497, 497, 517, 520, 523, 527, 527, 533, 533, 533, 537, 540, 547, 557, 563, 563, 567, 573, 583, 583, 590, 600, 633, 643
1. What is the minimum value in this data set? _____
2. What is the maximum value in this data set _____
3. What is the range for this data? ______________
Class(Intervals) Frequency
400-450
_______________
451-500
_______________
501-550
_______________
551-600
_______________
601-650
_______________

Sum:

_______________
4. Calculate the frequency using the classes (intervals) in the table above.  Include the class upper limit (CUL) in each class.
5. Sketch a histogram of the data, labeling your horizontal axis as appropriate.

6. What is the shape of the distribution? _____
7. What is the value of n for this data set? _____________
8. Find the mode of the data ___________
9. Find the median of the data ___________
10. Find the mean of the data given.___________
11. Find the sample standard deviation for the data _____.
12. Find the sample coefficient of variation for the date ____.
13. What is the value of n for this data set? _____________
3. Yap High School has a TOEFL average of 468 with a sample standard deviation of 70.   Weno High School has a TOEFL average of 371 with a sample standard deviation of 40.
1. Which school has the higher mean score?

2. Which school produces more consistent results, that is, which school produces students more consistently with a score close to the school average?

### Linear Regression

A student in SC 250 Botany notes that the Kalanchoe plant puts out one pair of leaves every month. The student also observes that the leaf blade continues to grow during the twelve month life span of a leaf blade. The student decides to study the leaf blade length and to determine statistical measures for the blades and their growth rate. The student gathers the following data:

Leaf blade age in months (x) Leaf blade length in cm (y)
2 16.0
3 16.5
4 15.5
5 17.0
6 17.3
7 17.2
8 17.2
9 17.0
10 18.4
11 18.0
12 18.5
1. _______ The slope of the least squares line represents the average rate of leaf blade growth per month in centimeters.  What is the slope of the least squares line?
2. _______ Use the least squares equation to predict the length of a leaf blade that is 10.5 months old.
3. _______ Use the least squares equation to predict the age of a leaf blade that is 17.4 cm long.
4. _______ The Pearson product-moment correlation will indicate whether the growth can be reasonably modeled by a linear equation.  What is the correlation r for the above data?
5. Is the correlation...
1. perfect negative correlation
2. highly negative correlation
3. moderately negative correlation
4. no correlation
5. moderately positive correlation
6. highly positive correlation
7. perfect positive correlation
6. _______ What is the Coefficient of Determination rē for the data above?

7. What does the Coefficient of Determination tell us for this model?

8. _______ Is the growth rate reasonably well modeled by a linear equation?
1. Why?