# Web Activities

Click on the following links. Please note these will open in a new window.

#### Conduct a significance test with confidence intervals

Go to this website: http://www.socscistatistics.com/confidenceinterval/Default3.aspx

In the activity section from Chapter 7, we had students report their commute time traveling to school this morning and compute the class average. Remember, in 2010, the U.S. census was able to determine that average commute time for U.S. adults. They determined that mean is μadults = 22.7, with a standard deviation of σ = 5.5. Given that the researchers believe that students differ in their commute averages, express the null hypothesis and use the above calculator to conduct a two-tailed significance test using a 95% confidence intervals. You can do this by determining whether μ0 falls within the interval.

Go to this website: http://www.socscistatistics.com/confidenceinterval/Default3.aspx

A recent study measured the differences in SAT scores across income categories. Interestingly they found that test-takers from the highest income category (> \$200,000) had the highest critical reading scores (M = 587, n = 81,586). Knowing the mean for the United States (μUS = 508, with a standard deviation of σ = 129), and given that the researchers believe that high income test-takers differ in their SAT scores, express the null hypothesis and use the above calculator to conduct a two-tailed significance test using a 95% confidence intervals. You can do this by determining whether μ0 falls within the interval.

#### Think of a simple question that you can post on social media and create a 95% confidence interval around m - μ0

Go to this website: http://www.socscistatistics.com/confidenceinterval/Default3.aspx

Think about a simple question you could ask your friends through social media. Before you ask the question, be sure to do some research and be sure you know the norms or the population average and standard deviation. Then, post you question online and compute the average for your social network. Knowing the mean for your question (based on your online research determine: μ = _____, with a standard deviation of σ = _____), and given that the you believe that your friends on this variable, express the null hypothesis and use the above calculator to conduct a two-tailed significance test using a 95% confidence intervals. You can do this by determining whether μ0 falls within the interval.