0
What is the qualifying time for the fastest 5 percent of all runners if the average finishing time is 5 minutes 17 seconds with standard deviation of 12 seconds?
Wiki User
∙ 6y ago
Assuming a normal distribution:
For the fastest 5% we need to find the z value which gives 100% - 5% = 95% of the area under the normal curve (from -∞).
Using single tailed tables, we need the z value which gives 95% - 50% = 0.45 (above the mean); this is found to be z ≈ 1.645
z = (value - mean)/standard deviation
→ value = mean + z × standard deviation
≈ 5 min 17 sec + 1.645 × 12 sec
≈ 5 min 17 sec + 20 s
= 5 min 37 sec
Wiki User
∙ 6y ago
Add your answer:
Earn +20 pts
Why use standard deviation and not average deviation?
Because the average deviation will always be zero.
What is the difference between standard deviation and mean?
The mean is the average value and the standard deviation is the variation from the mean value.
Sample standard deviation?
Standard deviation in statistics refers to how much deviation there is from the average or mean value. Sample deviation refers to the data that was collected from a smaller pool than the population.
What is percentile deviation?
A standard deviation in statistics is the amount at which a large number of given values in a set might deviate from the average. A percentile deviation represents this deviation as a percentage of the range.
Can a standard deviation of 4.34 be correct?
Yes, a standard deviation of 4.34 can be correct. Standard deviation is a measure of dispersion or variability in a data set. It represents the average amount by which individual data points deviate from the mean. Therefore, a standard deviation of 4.34 simply indicates that there is some variability in the data, with data points on average deviating by 4.34 units from the mean.
Why use standard deviation and not average deviation?
Because the average deviation will always be zero.
Does standard deviation and mean deviation measure dispersion the same?
No. The average of the deviations, or mean deviation, will always be zero. The standard deviation is the average squared deviation which is usually non-zero.
The standard deviation is the square root of the average squared deviation of scores from the?
mean
What is the difference between standard deviation and mean?
The mean is the average value and the standard deviation is the variation from the mean value.
How is standard deviation different from mean absolute decation?
If I have understood the question correctly, despite your challenging spelling, the standard deviation is the square root of the average of the squared deviations while the mean absolute deviation is the average of the deviation. One consequence of this difference is that a large deviation affects the standard deviation more than it affects the mean absolute deviation.
Why is it a useful value to report standard deviation?
The standard deviation of a distribution is the average spread from the mean (average). If I told you I had a distribution of data with average 10000 and standard deviation 10, you'd know that most of the data is close to the middle. If I told you I had a distrubtion of data with average 10000 and standard deviation 3000, you'd know that the data in this distribution is much more spread out. dhaussling@gmail.com
Sample standard deviation?
Standard deviation in statistics refers to how much deviation there is from the average or mean value. Sample deviation refers to the data that was collected from a smaller pool than the population.
What is deviation in statistics?
Deviation, actually called "standard deviation" is, in a set of numbers, the average distance a number in that set is away from the mean, or average, number.
Is variance the square root of standard deviation?
No, you have it backwards, the standard deviation is the square root of the variance, so the variance is the standard deviation squared. Usually you find the variance first, as it is the average sum of squares of the distribution, and then find the standard deviation by squaring it.
What is standard deviation divided by AVERAGE net income?
beta
In research how to define standard deviation?
Standard deviation shows how much variation there is from the "average" (mean). A low standard deviation indicates that the data points tend to be very close to the mean, whereas high standard deviation indicates that the data are spread out over a large range of values.
How is standard deviation useful?
It's used in determining how far from the standard (average) a certain item or data point happen to be. (Ie, one standard deviation; two standard deviations, etc.)
