Homework 8 - Due Wednesday 11/25:

1) Read chapter entitled “Confidence Interval Estimation” but only sections 1, 2 and 4

2) In that chapter do textbook problems 2, 12, 16, 32 and 42

3) A random sample of 8 SJSU students is taken. The ages of the students are 19,23,30,30,45,25,24,20
a. Using this data give a 90% confidence interval for the mean age of all SJSU students. Do NOT use Excel.
b. If a sample of 8 students is taken every year, how often will the resulting 90% confidence intervals contain the true population mean?
c. Are your answers to A and B correct even if the population of ages for the students is not normal? Why or why not?
d. Use Excel to check your answer for Part A.

4) a. Everything else being equal, which will be narrower: a 90% confidence interval or a 95% confidence interval?
b. Everything else being equal, which will be narrower: a confidence interval using a sample size of 1000 or a confidence interval using a sample size of 10,000?
c. Everything else being equal, which will be narrower: a confidence interval where the standard deviation is 10 or a confidence interval where the standard deviation is 3?


Homework 7 - Due Monday 11/16:

1) Read chapter entitled “The Normal Distribution and Other Continuous Distributions” but only sections 1, 5 and 6.

2) In that chapter do textbook problems 6, 8, 38 and 44.


Homework 6 - Due Monday 11/2:

1) Read chapter entitled “Some Important Discrete Probability Distributions” but only sections 1-3.

2) In that chapter do textbook problems 3, 4, 14, 15 and 20 (but skip part g in 20).

3) Stock X has a mean of $50 and a standard deviation of $10. Stock Y has a mean of $100 and a standard deviation of $20. Find the mean and standard deviation of buying one share of each
A) If they are independent (so the covariance is 0)
B) If the covariance is 30
C) If the covariance is -30


Homework 5 - Due Monday 10/12:

1) Read chapter entitled “Basic Probability”.

2) In that chapter do problems 4, 8, 12, 14, 17, 20, 23, 31 and 34.


Homework 4 - Due Monday 10/5:

1) Read chapter entitled “Numerical Descriptive Measures”.

2) In that chapter do textbook problems 5, 8 and 9 by hand AND check the answers using Excel.

3) The data at (http://www.cob.sjsu.edu/mease_d/freethrows.xls) gives free throw percentages for NBA basketball players for the 2005-2006 season.
a) Give the 5 number summary for the free throw percentages.
b) Graph the box-and-whisker plot by hand.
c) Based on your box-and-whisker plot, describe the shape of the data as left-skewed, symmetric or right-skewed.
d) Use Excel to compute the mean, variance and standard deviation.
e) Using your values from part d, give the empirical rule for this data.

4) Review In Class Exercise #46. (There will be one like this on the quiz.)


Homework 3 - Due Wednesday 9/23:

1) The dataset at http://www.cob.sjsu.edu/mease_d/sec4lettergrades.xls gives the letter grades for a quiz I gave once.
a) Make a summary table for the letter grades using the PivotTable in Excel. In your summary table list the grades in the order A+, A, A-, B+, etc. Double check a few of your answers by hand.
b) Make the bar chart using Excel with the grades in the same order as in part A.
c) Make the pie chart using Excel.
d) Make the pareto diagram using Excel.

2) The dataset http://www.cob.sjsu.edu/mease_d/America_West_Flights.xls contains flight status information for America West flights departing from four major West Coast airports. Make a contingency table for this data using the PivotTable feature in Excel.

3) Do textbook problem number 48 in Chapter “Presenting Data in Tables and Charts”.

4) The dataset at http://www.cob.sjsu.edu/mease_d/gpa-data.xls contains data from 20 San Jose State University graduating seniors who were asked to report their high school GPA (first column) and their current college GPA (second column).
a) Make a scatter plot of this data with High School GPA on the X-axis and College GPA on the Y-axis using Excel.
b) Give the equation of the least squares regression line using Excel.
c) What is the slope of the least squares regression line?
d) Interpret the slope of the least squares regression line.
e) What is the coefficient of correlation?
f) What is the value of R-squared?
g) Use the least squares regression line to predict the college GPA of a student who had a high school GPA of 2.7.

Important: Again, be sure to print out your solutions and bring them with you to class for the quiz.


Homework 2 - Due Wednesday 9/16:

1) Read the chapter entitled “Presenting Data in Tables and Charts”

2) The Excel file at http://www.cob.sjsu.edu/mease_d/old-quiz-scores.xls has Quiz 1 scores for a Bus 90 class I thought last semester. Right click this link and select "Save Target As..." to download this file onto your computer. Then open it using Excel.
a) Make the frequency distribution by hand. Begin at 0 and end at 22 using 11 intervals. (Hint: You may use Excel to sort the data first if you like).
b) Graph the frequency histogram by hand.
c) Graph the percentage polygon by hand.
d) Make the cumulative percentage distribution by hand.
e) Graph the ogive by hand.
f) Check your answer for part a using Excel.

3) The data at http://www.cob.sjsu.edu/mease_d/houses.xls has house prices for a sample of 1500 California homes. The prices are in thousands of dollars. Right click this link and select "Save Target As..." to download this file onto your computer. Then open it with Excel and use Excel to do the following. Be sure to print out your solutions and bring them with you to class for the quiz.
a) Make the frequency distribution using Excel. Begin at 0 and end at 3.5 million using 7 intervals.
b) Graph the percentage histogram using Excel.
c) Graph the percentage polygon using Excel.
d) Make the cumulative percentage distribution using Excel.
e) Graph the ogive using Excel.


Homework 1 - Due Monday 8/31:

1) Read the chapter entitled “Introduction and Data Collection”

2) In that chapter do textbook questions 2, 3, 8(b), 14 (skip a), 16 (skip a), 18

(Note: Answers to textbook questions with even numbers are given in the book. Also, you will need to use Table 1 in the back of the book.)