Studied by 3 people
Looks like no one added any tags here yet for you.
1. What is the appropriate denotation for variance?
φ¯ for population, v¯ for sample
μ2 for population, s2 for sample
σ2 for population, s2 for sample
VAR for population, var for sample
σ2 for population, s2 for sample
2. Two data sets have the same size, but Data set A has a sum of squares of 97 and Data set B has a sum of squares of 197. In which data set are the data values more widely spread out?
Data set B, because 197 can have more variation than 97.
Data set A, because a sum of squares of 97 is smaller than a sum of squares of 197.
Data set A, because 97 is closer to zero than 197.
Data set B, because a sum of squares of 197 is bigger than a sum of squares of 97.
Data set B, because a sum of squares of 197 is bigger than a sum of squares of 97.
In statistics, a deviation applies to only one data value. true/false
true
4. Match the appropriate statistic for a distribution of efficient statistics.
Answer has been selected.
A. Standard deviation.
B. Mean.
C. Histogram.
Shape.
Location.
Spread.
Spread
Location.
Shape
5. The mean (µ) is NOT needed to calculate a deviation. true/false
false
A deviation can never equal zero. true/false
false
7. Does the average deviation always equal zero for every data set?
Yes, because the deviations cluster about the mean.
Yes, because the positive and negative deviation cancel each other.
No, because this is not true.
No, because the average deviation equals zero for some data sets, but not for all datasets.
Yes, because the positive and negative deviation cancel each other.
8. Match the appropriate set of statistics to the descriptions below.
Answer has been selected.
A. Resistant statistics.
B. Efficient statistics.
Extract the most information from a column of data
Less affected by extreme values
Less affected by extreme values
Extract the most information from a column of data
9. Variance (σ2) is what type of measure of spread?
A raw measure of spread.
A measure of spread normalized for shape.
A measure of spread adjusted for bias.
A measure of spread standardized for the number of data values.
A measure of spread standardized for the number of data values.
10. How is the sum of squares (SS) standardized into variance (σ2)?
Divide by the number of data values.
Divide by the degrees of freedom.
Take the square-root of the sum of squares.
Sum of squares is the same value as the variance.
Divide by the degrees of freedom.
11. Which one of the following answers is NOT correct about standard deviation?
Standarddeviation= √σ^2
Standarddeviation= √Variance
Standarddeviation^2= Variance−
Standarddeviation =Variance^2
Standard deviation = Variance^2
12. Does the sum of squares (SS) usually get bigger as more data values are added to the data set?
Yes, because there are more numbers in the data set to sum.
Yes, because bigger data sets must have bigger sum of squares than smaller data sets.
No, because the new data values could have negative squares.
No, because the sum of squares is adjusted for the number of data values in the data set.
Yes, because there are more numbers in the data set to sum.
13. What is the appropriate denotation for standard deviation?
s population, σ for sample.
σ for population, std for sample.
µ for population, s for sample
σ for population, s for sample.
σ for population, s for sample.
14. What information about a data value is given by its deviation?
The statistical distance and direction from the mean.
The mathematical distance and direction from the mean.
The magnitude (absolute value) of the difference between the data value and the median.
How different the data value is from the mean and median.
The mathematical distance and direction from the mean.
15. What is the statistical term for all the squared deviations added together?
Sum of squares.
Variance.
Standard deviation.
Root mean square.
Sum of squares.
16. A bigger standard deviation for a data set means the data values are?
Spread wider apart.
Spread narrower together.
Spread more evenly about the mean.
Have a more symmetrical spread.
Spread wider apart.
17. The efficient measure of spread for a column of data is the?
Average deviation.
Standard deviation.
Middle deviation.
The average of all the deviation in the data set.
Standard deviation.
18. The mean (µ) is used when thinking about the data values in a column of data because? (select two of the answers below)
Select Answer(s)
The mean is easier to calculate than the median.
The mean can be used in advanced statistical methods.
A single number is easy to think about.
The mean best represents the values in the column of data.
A single number is easy to think about.
The mean best represents the values in the column of data.
19. A data value less than the mean has a?
Positive deviation.
Left deviation.
Negative deviation.
None of the above
Negative deviation.
20. The sum of squares (SS) is what type of measure of spread?
A standardized measure of spread.
A normalized measure of spread.
A raw measure of spread.
An adjusted measure of spread.
A raw measure of spread.
21. What is the formula for the sum of squares (SS)?
Sum of squares = ∑(x−xbar)2
22. Can the standard deviation (σ) be used to find probability?
Yes, it can with a normal curve.
Yes, because it is part of a distribution.
No, because the average deviation is used.
No, because spread is not needed to find probability.
Yes, it can with a normal curve.
23. A data value close to the mean has a?
Large deviation.
Small deviation.
No deviation.
Middle deviation.
Small deviation.
24. Is the average deviation better than the standard deviation (σ)?
No, because the standard deviation is a standardized version of the average deviation.
Yes, because the average is the most representative value.
No, because the average deviation always equals zero.
Yes, because the average deviation is much quicker to calculate and much easier to use.
No, because the average deviation always equals zero.
25. To calculate variance, statistics does not average the deviations, instead it averages the?
The positive and negative deviations separately.
Squared deviations.
The square-root of the squared deviations.
The absolute value of the deviations.
Squared deviations.
Note 
Flashcard (28)