Affluent Savvy
Photo by KoolShooters Pexels Logo Photo: KoolShooters

What is the 95% confidence rule?

With a 95 percent confidence interval, you have a 5 percent chance of being wrong. With a 90 percent confidence interval, you have a 10 percent chance of being wrong. A 99 percent confidence interval would be wider than a 95 percent confidence interval (for example, plus or minus 4.5 percent instead of 3.5 percent).

What flower is a symbol of wealth?
What flower is a symbol of wealth?

Peonies. Peony is one of the flowers that symbolize prosperity, wealth and good fortune. Aside from that, it also symbolizes dignity, honor and...

Read More »
Which zodiac likes to be single?
Which zodiac likes to be single?

Generally, people like Cancer and Taurus love to be in committed relationships, as they adore the sweetness of being in love and having a steady...

Read More »

Confidence Intervals - Statistics Teaching Tools

What is a confidence interval?

A confidence interval is a range around a measurement that conveys how precise the measurement is. For most chronic disease and injury programs, the measurement in question is a proportion or a rate (the percent of New Yorkers who exercise regularly or the lung cancer incidence rate). Confidence intervals are often seen on the news when the results of polls are released. This is an example from the Associate Press in October 1996: The latest ABC News-Washington Post poll showed 56 percent favored Clinton while 39 percent would vote for Dole. The ABC News-Washington Post telephone poll of 1,014 adults was conducted March 8-10 and had a margin of error of plus or minus 3.5 percentage points. (Emphasis added). Although it is not stated, the margin of error presented here was probably the 95 percent confidence interval. In the simplest terms, this means that there is a 95 percent chance that between 35.5 percent and 42.5 percent of voters would vote for Bob Dole (39 percent plus or minus 3.5 percent). Conversely, there is a 5 percent chance that fewer than 35.5 percent of voters or more than 42.5 percent of voters would vote for Bob Dole. The precise statistical definition of the 95 percent confidence interval is that if the telephone poll were conducted 100 times, 95 times the percent of respondents favoring Bob Dole would be within the calculated confidence intervals and five times the percent favoring Dole would be either higher or lower than the range of the confidence intervals. Instead of 95 percent confidence intervals, you can also have confidence intervals based on different levels of significance, such as 90 percent or 99 percent. Level of significance is a statistical term for how willing you are to be wrong. With a 95 percent confidence interval, you have a 5 percent chance of being wrong. With a 90 percent confidence interval, you have a 10 percent chance of being wrong. A 99 percent confidence interval would be wider than a 95 percent confidence interval (for example, plus or minus 4.5 percent instead of 3.5 percent). A 90 percent confidence interval would be narrower (plus or minus 2.5 percent, for example).

What does a confidence interval tell you?

How can I use cinnamon to get pregnant fast?
How can I use cinnamon to get pregnant fast?

You can sprinkle some freshly ground cinnamon onto your food every morning, or you can take a daily dose of honey and cinnamon to conceive. Other...

Read More »
How much is a zinc 1943 penny worth?
How much is a zinc 1943 penny worth?

Because they are quite common, a 1943 penny in circulated condition is not worth much. According to USA Coin Book, a steel penny from 1943 in...

Read More »
Awaken your dormant DNA ability to attract wealth effortlessly
Awaken your dormant DNA ability to attract wealth effortlessly

The simple yet scientifically proven Wealth DNA method laid out in the report allows you to effortlessly start attracting the wealth and abundance you deserve.

Learn More »

he confidence interval tells you more than just the possible range around the estimate. It also tells you about how stable the estimate is. A stable estimate is one that would be close to the same value if the survey were repeated. An unstable estimate is one that would vary from one sample to another. Wider confidence intervals in relation to the estimate itself indicate instability. For example, if 5 percent of voters are undecided, but the margin of error of your survey is plus or minus 3.5 percent, then the estimate is relatively unstable. In one sample of voters, you might have 2 percent say they are undecided, and in the next sample, 8 percent are undecided. This is four times more undecided voters, but both values are still within the margin of error of the initial survey sample. On the other hand, narrow confidence intervals in relation to the point estimate tell you that the estimated value is relatively stable; that repeated polls would give approximately the same results.

How are confidence intervals calculated?

Confidence intervals are calculated based on the standard error of a measurement. For sample surveys, such as the presidential telephone poll, the standard error is a calculation which shows how well the poll (sample point estimate) can be used to approximate the true value (population parameter), i.e. how many of the people surveyed said they would vote for Dole versus how many people actually would vote for Dole in the election. Generally, the larger the number of measurements made (people surveyed), the smaller the standard error and narrower the resulting confidence intervals. Once the standard error is calculated, the confidence interval is determined by multiplying the standard error by a constant that reflects the level of significance desired, based on the normal distribution. The constant for 95 percent confidence intervals is 1.96.

Is confidence a gift from God?
Is confidence a gift from God?

God gives us the capacity, confidence, and courage to do right. Even a glimpse of the supremacy of God and our inseparable relation to Him...

Read More »
How can I make a 1m year in real estate?
How can I make a 1m year in real estate?

How To Make A Million Dollars In Real Estate Learn About Real Estate Investing. Establish Your Goals. Start Now, But Start Small. Write Offers For...

Read More »
Awaken your dormant DNA ability to attract wealth effortlessly
Awaken your dormant DNA ability to attract wealth effortlessly

The simple yet scientifically proven Wealth DNA method laid out in the report allows you to effortlessly start attracting the wealth and abundance you deserve.

Learn More »
Which zodiac is the most genuine?
Which zodiac is the most genuine?

Capricorn Capricorn They are always honest and genuine about their feelings and intentions. Thus, these are one of the most genuine zodiac signs on...

Read More »
Awaken your dormant DNA ability to attract wealth effortlessly
Awaken your dormant DNA ability to attract wealth effortlessly

The simple yet scientifically proven Wealth DNA method laid out in the report allows you to effortlessly start attracting the wealth and abundance you deserve.

Learn More »
What is a 75 year period called?
What is a 75 year period called?

Diamond Jubilee: Celebrating 75 years in 1948. Centennial: Celebrating 100 years in 1970. Quasquicentennial: Celebrating 125 years in 1995.

Read More »