Stats Chapter 3

The sum of deviation of the individual data elements from their mean is always _____

0

If standard deviation is 8 and coefficient of variation is 64%, then the mean would then be ________

12.5

The variance of a sample of 169 observations equals 576. The standard deviation of the sample equals _____

24

The 75th percentile is referred to as the ______

3rd quarter

The heights of 25 individuals were recorded and the following statistics were calculated: mean is 70, mode is 73, median is 74, range is 20, variance is 784. The coefficient of variation equals _____

40%

If the coefficient of variation is 40% and the mean is 70, then the variance is equal to ________

784

The variance of a sample of 81 observations equals 64. The standard deviation of the sample equals ______

8

Since the mode is the most frequently occurring data value, it is always ______ than the mean

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Since the population size is always larger than the sample size, then the sample statistic is always _________ compared to the population parameter

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What are two numerical measures of the linear association between two variables?

Sxy and rxy

What symbol represents the size of the population?

N

What are the two steps of how the median is calculated, if a data set has an even number of observations?

Put them in order and take the average of the middle two

The interquartile range is ______

Q3-Q1

The sample variance is always larger or smaller or the same as the population variance

all of the above

The median is a measure of _____ _______

central location

The coefficient of correlation can never be _______ or ________

greater than 1; less than 1

The most important statistical descriptive measure of the central location of a data set is the _______

mean

List the three measures of central location

mean, median, mode

The value which has half of the observations above it and half the observations below it is called the ______

median

What symbol represents the mean of the population?

mu

In computing the mean of a sample, the value of sigma xi is divided by _____

n

What symbol represents the size of the sample?

n

The variance can never be ________

negative

The variance of the sample can never be _______

negative

The symbol o2 is used to represent ______ ________

population variance

The difference between the largest and the smallest data values is the _____

range

The measure of dispersion that is influenced most by extreme values is the _______

range

When the data are skewed to the right, the longer tail of the distribution is on the _____

right

The descriptive measure of dispersion that is based on the concept of a deviation about the mean is _________

the variance

List the four measures of dispersion

variance, standard deviation, range, and IQR (interquartile range)

The mean of a sample is computed by summing _______ and then dividing by _______

xi; n