http:/www.avert.org/safricastats.htm
The statistics discussed here come from two prevalence studies that estimate how many South Africans have HIV, and two reports on AIDS deaths. Viewed together these sources give an idea of the scale of South Afri
STAT 226
Homework 1
Due Tuesday, February 5th in Class
SHOW ALL YOUR WORK FOR FULL CREDIT! PRINT AND TURN IN JMP OUTPUT AS INDICATED!
Carefully read the Homework Guidelines that can be found on the course web page for all Stat 226 sections (see a
Introduction
Chapter 11
Multiple Regression
We have investigated the relationship between a pair of quantitative variables with simple linear regression (Chapter 2) and inference for regression (Chapter 10). Multiple regression (Chapter 11) concer
Homework 5
Stat 226
Fall 2015
This homework project focuses on the sampling distribution of the sample mean and the
Central Limit Theorem (CLT).
Before beginning with the assignment, lets remind ourselves of the Central Limit Theorem (CLT)
and why it is u
Name:
Class Number:
UnivID:
EXAM II STAT 226 Section C/D FORM A
Fall 2013
Show all your work and write complete and coherent answers.
You must show your ISU student ID card or drivers license if asked.
You should bring to the exam a calculator capable
The following problems are intended as exam review!
A confidence interval for the population mean
1. Backward Normal Calculations for X.
is essentially a backwards Normal calculation from the sampling distribution of the sample
mean. Suppose the distribu
Questions (and Answers) on Hypothesis Tests _, - . .1
STAT226F, Fall 2015 - 11/6/2015 I
Setting up hypotheses .
e What does He mean?
pois just a symbol representing the value of the mean you are using in the hypotheses. Suppose
we are testing a less tha
Homework 4 Solutions
Stat 226
Spring 2016
A manufacturer of automobile
1. [9 pts.] Describing the Sampling Distribution of X.
batteries claims that the length of life for their batteries is normally distributed with a mean of
40 months and a standard dev
Woxrlsheet 5
ST AT LT-6 L
Stat 226 Normal Calculations
NCAA rules for athletes. The National Collegiate Athletic Association (NCAA)
requires Division I athletes to score at least 820 on the combined mathematics and verbal
parts of the SAT exam to compete
Homework 5B
due: October 25th 7pm
stat 226
Fall 2016
1. Critical Values from the t-table (Table D).
(a) Accurate to the nearest 3 decimal places, what is the critical value (t or z ) that corresponds to the given confidence levels and degrees of freedom.
Homework 1
Stat 226
Fall 2016
due September 1st
at 7pm in Blackboard
Instructions: Every homework assignment will consist of two parts:
Part 1: Automated grading/numerical response assessment
Part 2: Free response assessment
Unless indicated otherwise,
Homework 2 Solution KEY
Stat 226
Fall 2016
Total Points: 39.5
1. Categorical or Quantitative? Classify each variable as categorical or quantitative.
(a)
(b)
(c)
(d)
(e)
Social Security number of an Apple employee. Categorical
Apples annual net profit. Qua
Stat 226
Fall 2016
Homework 1 Solution
Total Points: 50
1. Presidential Election. [4 pts] This Fall the United States will elect its 45th president. The
Republican and Democratic party presidential hopefuls have been campaigning relentlessly in
an effort
homework 5b solutions
due: October 27th 7pm
stat 226
fall 2016
1. Critical Values from the t-table (Table D).
(a) Accurate to the nearest 3 decimal places, what is the critical value (t or z ) that corresponds to the given confidence levels and degrees of
Homework 8
Stat 226
Fall 2015
1. Stating the hypotheses. In each of the following situations a significance test for a population
mean is called for. Identify the null hypothesis H0 and the alternative hypothesis HA in each
case. Make sure to use proper n
Homework 6
Stat 226
Fall 2015
DUE OCTOBER 29th
AT 7PM IN BLACKBOARD
1. For this question refer to the figure below (or to the handout CI-Simulation), which displays
two separate plots. Below are a few bullet points to describe the plots.
0.5
0.5
95 % with
Exam 2 Stat 226 FORM A
Page 2
1. [ 10pts.] TRUE or FALSE: Identify which of the following are valid statements.
(a) T F The sampling distribution of the sample mean is not needed when we make inference about
the population mean .
(b) T F Confidence interv
#utf-8#Warning
#C#7This data table had been saved in a more recent
format.#BIt is not compatible with the format known to this version of
JMP.#Please do not save this table#ASaving
this table with this version of JMP will destroy the
data.#`#a#utf-8#@.L#A
Stat 226
Spring 2015
Homework 3
Instructions for HW 3 : Report z-scores upto 2 decimal places.
Report final probability upto 4 decimal places.
Always enter only the number in BB. For eg. if your answer is 100 hours then enter only 100 in
BB. If your ans
Homework 9
Stat 226
Spring 2015
Due Date On-Campus: Thurs April 23 @7p
Due Date Off-campus: Thurs April 23 @7p
1. True or False? For each of the following statements, choose either true or false.
T
F
In a scatterplot, the response is shown on the horizont
Homework 8
Stat 226
Spring 2015
1. Stating the hypotheses. In each of the following situations a significance test for a population
mean is called for. Identify the null hypothesis H0 and the alternative hypothesis HA in each
case. Make sure to use proper
Homework 2
Stat 226
Spring 2015
1. Categorical or Quantitative? Classify each variable as categorical or quantitative. Hint:
Sometimes deciding between categorical and quantitative is not as straightforward as we would
hope. As a rule of thumb, think abou
Exam 2 Stat 226 FORM A
Page 2
1. [9pts.] TRUE or FALSE: Identify which of the following are valid statements.
(a) T F The sampling distribution of the sample mean is not needed when we make inference about
the population mean .
(b) T F Confidence interval
STAT226F, Fall 2015
Module 6 Part 2: Chapter 15
Confidence Intervals for when is unknown
Review/Motivation
o We can use a sample to calculate a confidence interval for the
population mean, , provided the following conditions are met:
o When the above con
Stat 226
Fall 2016
Homework 6
due November 8th
at 7pm in Blackboard
1. Stating the hypotheses. In each of the following situations a significance test for a population
mean is called for. Identify the null hypothesis H0 and the alternative hypothesis Ha i
Homework 3
Stat 226
Fall 2016
due September 22nd
at 7pm in Blackboard
Homework 3 Specific Instructions: Recording numerical answers:
Report z-scores to the nearest 2 decimal places.
Report final probability as a proportion (NOT a percent) to the nearest
STAT226 F, Fall 2015
Module 2: Chapter 4
Chapter 4: Describing Numerical Data
Histograms
o Histogram: one of the most common ways to summarize
observations from a quantitative variable. Histograms display the
distribution of the numerical variable under
STAT226F, Fall 2015
Module 4: Extra Notes
Toward Statistical Inference
Recall our overall goal: to use data (sample) to infer information about an
unknown population parameter, such as the population mean, .
Difference between , , and :
o The population