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The confidence interval consists of a central value and a margin of error around that value. If it is an X% confidence interval then there is a X% probability that the true value of the statistic in question lies inside the interval. Another way of looking at it is that if you took repeated samples and calculated the test statistic each time, you should expect X% of the test statistics to fall within the confidence interval.
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What Happens To The Width Of The Confidence Interval If You Decrease The Confidence Level Decrease The Sample Size or Decrease the margin of error?
The width of the confidence interval willdecrease if you decrease the confidence level,increase if you decrease the sample sizeincrease if you decrease the margin of error.
What is meant by a 95 percent confidence interval?
Confidence IntervalsConfidence interval (CI) is a parameter with a degree of confidence. Thus, 95 % CI means parameter with 95 % of confidence level. The most commonly used is 95 % confidence interval.Confidence intervals for means and proportions are calculated as follows:point estimate ± margin of error.
What happens to the confidence interval if you increase the margin of error?
It depends on whether it is the Type I Error or the Type II Error that is increased.
Compute the population mean margin of error for a 90 percent confidence interval when sigma is 4 and the sample size is 36?
1.0966
What are the advantages of a small confidence interval in statistics?
The smaller the confidence interval, the more certain you are of the answers. Remember confidence level and confidence interval (margin of error) are 2 separate things. So if you are using an industry standard confidence level of 95% and 5% margin of error in a standard statistical table, then you could say, for example, with 95% certainty that 60% of those polled would vote for John McCain. Another way of saying this is even though you did not poll everyone (if you did, it would then become a very expensive census), you can say with a high degree of certainty (95% certainty) that 55% to 65% of those polled will vote for Johnny (sadly).
How do you find The margin of error for the confidence interval is?
Generally speaking an x% confidence interval has a margin of error of (100-x)%.
The width of a confidence interval is equal to twice the value of the margin of error?
No. The width of the confidence interval depends on the confidence level. The width of the confidence interval increases as the degree of confidence demanded from the statistical test increases.
What Happens To The Width Of The Confidence Interval If You Decrease The Confidence Level Decrease The Sample Size or Decrease the margin of error?
The width of the confidence interval willdecrease if you decrease the confidence level,increase if you decrease the sample sizeincrease if you decrease the margin of error.
What happens to the confidence interval as the standard deviation of a distribution increases?
The standard deviation is used in the numerator of the margin of error calculation. As the standard deviation increases, the margin of error increases; therefore the confidence interval width increases. So, the confidence interval gets wider.
What determines an election poll's margin of error?
The confidence interval radius determines the margin of error. If you want more information visit: http://en.wikipedia.org/wiki/Margin_of_error
In a poll of 100 adults 45 percent reported they believe in faith healing If the poll was based on 5000 adults would the confidence interval be wider or narrower?
The formula for margin of error is (Z*)*(Standard Deviation))/(sqrt(N)), so as N increases, the margin of error decreases. Here N went from 100 to 5000, so N has increased by 4900. This means the margin of error decreases. Since the confidence interval is the mean plus or minus the margin of error, a smaller margin of error means that the confidence interval is narrower.
99 percent confidence interval Population mean 24.4 to 38.0 find the mean sample?
if the confidence interval is 24.4 to 38.0 than the average is the exact middle: 31.2, and the margin of error is 6.8
What is meant by a 95 percent confidence interval?
Confidence IntervalsConfidence interval (CI) is a parameter with a degree of confidence. Thus, 95 % CI means parameter with 95 % of confidence level. The most commonly used is 95 % confidence interval.Confidence intervals for means and proportions are calculated as follows:point estimate ± margin of error.
What happens to the confidence interval if you increase the margin of error?
It depends on whether it is the Type I Error or the Type II Error that is increased.
Compute the population mean margin of error for a 90 percent confidence interval when sigma is 4 and the sample size is 36?
1.0966
Does increasing the margin of error decrease the length of the confidence interval?
It depends on whether it is the Type I Error or the Type II Error that is increased.
Compute the population mean margin of error for a 99 percent confidence interval when sigma is 4 and the sample size is 36?
The mean plus or minus 2.576 (4/sqr.rt. 36)= 1.72 So take your average plus or minus 1.72 to get your confidence interval
