Title: Confidence intervals
Headings: Confidence intervals
Confidence intervals
How confidence intervals are used
What factors influence a confidence interval?
Why are confidence intervals important?

Content: What factors influence a confidence interval? A narrow or small confidence interval indicates that if we were to ask the same question of a different sample, we are reasonably sure we would get a similar result. A wide confidence interval indicates that we are less sure and perhaps information needs to be collected from a larger number of people to increase our confidence. Confidence intervals are influenced by the number of people that are being surveyed. Typically, larger surveys will produce estimates with smaller confidence intervals compared to smaller surveys. Other factors will include the accuracy of the measurements in a survey. If measurements are less accurate, it will likely increase confidence intervals. Why are confidence intervals important? Because confidence intervals represent the range of scores that are likely if we were to repeat the survey, they are important to consider when generalizing results. In the example with Mr. Miller, how confident would you be in saying that more than half of Torontonians would vote for Miller?