SPSS program

STAT 509 Assignment# 4 Name_______________________

Instructions:

1) Due Date

· April 27 @ 11:50pm

2) Assignment submission:

· When you submit an electronic file (assignment) you must use the following format: This is for: LAST NAME (in upper case), your first name, the course code, activity/assignment number and file format

· For example: SMITHJohn-STAT509-A1.doc

Assignment: (show your work)

1. Starting salaries of college graduates who have taken a statistics course: 95% confidence level; n= 28, the mean of the sample = $45,678, the population is normally distributed, and standard deviation of the population is known to be $9,900.

2. IQ scores of statistics student: 95% confidence level; n =32, the mean of the sample = 117.2, standard deviation of the sample (s)= 12.1.

3. Use the sample data and confidence level to construct the confidence interval estimate of the population proportion

· If n= 400, x= 300, 95% confidence

· If n=2001, x=1776, 90% confidence

4. A researcher wishes to estimate, with 95% confidence, the proportion of people who own a home computer. A previous study shows that 40 of those interviewed had a computer at home. The research wishes to be accurate within 2 % of the true proportion. Find the minimum size necessary.