# Web Activities

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

#### Determine the 95% Confidence interval around satisfaction with life

Go to this website: https://www.mathsisfun.com/data/confidence-interval-calculator.html

When measures an individual’s satisfaction with life, many people use The Satisfaction with Life Scale (Diener, Emmnos, Larsen, and Griffin, 1985) because it was developed, specifically, as a cognitive assessment of subjective well-being (or happiness). In the original paper, 176 undergraduate completed the five-item scale and the mean on the SWLS was 25.5 (possible range 5–35), with a standard deviation of 6.43. Use this calculator to determine various approximate confidence intervals around the mean (80%, 90%, 95%, and 99%). Report the answers in APA style. What happens as you change the confidence level?

#### Determine the 95% Confidence interval around any psychology construct

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

Go to Google Scholar and search for a psychological construct you find interesting (e.g., Authenticity, depression, grit, etc.). Find an article that reports the sample mean, sample standard deviation, and sample size for the construct you are interested in understanding. Use this calculator to determine various approximate confidence intervals around the mean (80%, 90%, 95%, and 99%). Report the answers in APA style. What happens as you change the confidence level?

#### Determine the sample size needed to obtain your desired Confidence interval

Go to this website: http://www.sample-size.net/sample-size-conf-interval-mean/

The previous web exercise showed you how to determine the 95% CI around any psychological construct. Now, assume you want to conduct a new study and you would like to know the sample needed to obtain your desired confidence interval. The website above will help you determine your required sample size. Use the confidence intervals from your computations above (or a new CI) determine the sample size you need for your future study.