Math 143 C/E, Spring 2001
IPS Reading Questions
Chapter 7, Section 1 (pp. 502-507; up to The one-sample
t test)
After closing up the previous applet, click here and here to start up applets in two more windows. One applet draws the student t distribution, allowing you to set the degrees of freedom and move sliders around to highlight (in yellow) the region whose area you want to know. The other applet is similar, but uses the standard normal distribution. Set the degrees of freedom to 1 for the student t curve, and highlight the region between 0 and 1 (these values located along the horizontal axis). Compare the percentage of area between 0 and 1 for the two curves. Keep raising the number of degrees of freedom for the t curve until the amount of area is pretty much the same. What was the least number of degrees of freedom required? If you consider the area between 0 and 2 at this number of degrees of freedom, is it still the same?
df | C | t* |
17 | 90% | |
28 | 99.5% | |
80 | 98% |