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75 Cards in this Set
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Observations (such as measurements, genders, survey responses) that have been collected.

DATA


A collection of methods for planning studies and experiments, obtaining data, and then organizing, summarizing, presenting, analyzing, interpreting, and drawing conclusions based on the data.

STATISTICS


The complete collection of all elements (scores, people, measurements, and so on) to be studied. The collection is complete in the sense that it includes all subjects to be studied.

POPULATION


The collection of data from every member of the population.

CENSUS


A subcollection of members selected from a population.

SAMPLE


Sample data must be collected in an appropriate way, such as through a process of _____ selection.

RANDOM


A numerical measurement describing some characteristic of a population.

PARAMETER


A numerical measurement describing some characteristic of a sample.

STATISTIC


In New York City, there are 3250 walk buttons that pedestrians can press at traffic intersections. It was found that 77% of those buttons do not work. The figure of 77% is a _____ because it is based on the entire population of all 3250 pedestrian push buttons.

PARAMETER


Based on a sample of 877 surveyed executives, it is found that 45% of them would not hire someone with a typographic error on their job application. That figure of 45% is a _____ because it is based on a sample, not the entire population of all executives.

STATISTIC


_____ consist of numbers representing counts or measurements.

QUANTITATIVE DATA


_____ can be separated into different categories that are distinguished by some nonnumeric characteristic.

QUALITATIVE (OR CATEGORICAL OR ATTRIBUTE) DATA


The weights of supermodels is an example of _____.

QUANTITATIVE DATA


The genders (male/female) of professional athletes is an example of _____.

QUALITATIVE DATA


_____ result when the number of possible values is either a finite number or a "countable" number. (That is, the number of possible values is 0 or 1 or 2, and so on.)

DISCRETE DATA


_____ result from infinitely many possible values that correspond to some continuous scale that covers a range of values without gaps, interruptions, or jumps.

CONTINUOUS (NUMERICAL) DATA


The numbers of eggs that hens lay are _____ because they represent counts.

DISCRETE DATA


The amounts of milk from cows are _____ because they are measurements that can assume any value over a continuous span. During a given time interval, a cow might yield an amount of milk that can be any value between 0 gallons and 5 gallons. It would be possible to get 2.343115 gallons because the cow is not restricted to the discrete amounts of 0, 1, 2, 3, 4, or 5 gallons.

CONTINUOUS DATA


The _____ is characterized by data that consist of names, labels, or categories only. The data cannot be arranged in an ordering scheme (such as low to high).

NOMINAL LEVEL OF MEASUREMENT


Survey responses of yes, no, and undecided are an example of _____.

NOMINAL LEVEL OF MEASUREMENT


The colors of cars driven by college students (red, black, blue, white, magenta, mauve, and so on) are an example of _____.

NOMINAL LEVEL OF MEASUREMENT


Data are at the _____ if they can be arranged in some order, but differences between data values either cannot be determined or are meaningless.

ORDINAL LEVEL OF MEASUREMENT


A college professor assigns grades of A, B, C, D, or F. These grades can be arranged in order, but we can't determine differences between such grades. This is an example of _____.

ORDINAL LEVEL OF MEASUREMENT


Based on several criteria, a magazine ranks cities according to their "livability." Those ranks (first, second, third, and so on) determine an ordering. However, the differences between ranks are meaningless. This is an example of _____.

ORDINAL LEVEL OF MEASUREMENT


The _____ is like the ordinal level, with the additional property that the difference between any two data values is meaningful. However, data at this level do not have a natural zero starting point (where none of the quantity is present).

INTERVAL LEVEL OF MEASUREMENT


Body temperatures of 98.2F and 98.6F are examples of data at this _____. Those values are ordered, and we can determine their difference of 0.4F. However, there is no natural starting point. The value of 0F might seem like a starting point, but it is arbitrary and does not represent the total absence of heat.

INTERVAL LEVEL OF MEASUREMENT


The years 1000, 2008, 1776, and 1492 are an example of this _____. (Time did not begin in the year 0, so the year 0 is arbitrary instead of being a natural zero starting point representing "no time.")

INTERVAL LEVEL OF MEASUREMENT


The _____ is the interval level with the additional property that there is also a natural zero starting point (where zero indicates that none of the quantity is present). For values at this level, differences and ratios are both meaningful.

RATIO LEVEL OF MEASUREMENT


Weights (in carats) of diamond engagement rings (0 does represent no weight, and 4 carats is twice as heavy as 2 carats) is an example of ______.

RATIO LEVEL OF MEASUREMENT


Prices of college textbooks ($0 does represent no cost, and a $90 book is three times as costly as a $30 book) is an example of this _____.

RATIO LEVEL OF MEASUREMENT


A representative or average value that indicates where the middle of the data set is located.

CENTER


A measure of the amount that the data values vary among themselves.

VARIATION


The nature or shape of the distribution of the data (such as bellshaped, uniform, or skewed).

DISTRIBUTION


Sample values that lie very far away from the vast majority of the other sample values.

OUTLIERS


Changing characteristics of the data over time.

TIME


A _____ lists data values (either individually or by groups of intervals), along with thier corresponding frequencies (or counts).

FREQUENCY DISTRIBUTION (OR FREQUENCY TABLE)


_____ are the smallest numbers that can belong to the different classes.

LOWER CLASS LIMITS


_____ are the largest numbers that can belong to the different classes.

UPPER CLASS LIMITS


_____ are the numbers used to separate classes, but without the gaps created by class limits.

CLASS BOUNDARIES


_____ are the values in the middle of the classes. Can be found by adding the lower class limit to the upper class limit and dividing the sum by 2.

CLASS MIDPOINTS


_____ is the difference between two consecutive lower class limits or two consecutive lower class boundaries.

CLASS WIDTH


_____ is found by dividing each class frequency by the total of all frequencies.

RELATIVE FREQUENCY


A _____ includes the same class limits as a frequency distribution, but relative frequencies are used instead of actual frequencies.

RELATIVE FREQUENCY DISTRIBUTION


The _____ for a class is the sum of the frequencies for that class and all previous classes.

CUMULATIVE FREQUENCY


The frequencies start low, reach a peak, then become low again.

NORMAL DISTRIBUTION


A bar graph in which the horizontal scale represents classes of data values and the vertical scale represents frequencies. The heights of the bars correspond to the frequency values, and the bars are drawn adjacent to each other (without gaps).

HISTOGRAM


The scale of a histogram that uses class boundaries or class midpoints.

HORIZONTAL SCALE


The scale of a histogram that uses class frequencies.

VERTICAL SCALE


A _____ has the same shape and horizontal scale as a histogram, but the vertical scale is marked with relative frequencies instead of actual frequencies.

RELATIVE FREQUENCY HISTOGRAM


The method of statistics that summarizes or describes the important characteristics of a set of data.

DESCRIPTIVE STATISTICS


The method of statistics that uses sample data to make inferences (or generalizations) about a population.

INFERENTIAL STATISTICS


A _____ is a value at the center or middle of a data set.

MEASURE OF CENTER


The _____ of a set of values is the measure of center found by adding the values and dividing the total by the number of values.

ARITHMETIC MEAN


NOTATION: Denotes the sum of a set of values.

E


NOTATION: Is the variable usually used to represent the individual data values.

x


NOTATION: Represents the number of values in a sample.

n


NOTATION: Represents the number of values in a population.

N


NOTATION: Is the mean of a set of sample values.

xbar = Ex/n


NOTATION: Is the mean of all values in a population.

mu (upside down h) = Ex/N


The _____ of a data set is the measure of center that is the middle value when the original data values are arranged in order of increasing (or decreasing) magnitude.

MEDIAN (OFTEN DENOTED BY XTILDE)


The _____ is the measure of center that is the value midway between the maximum and minimum values in the original data set. It is found by adding the maximum data value to the minimum data value and then dividing the sum by 2.

MIDRANGE


A simple rule for rounding answers is this:

CARRY ONE MORE DECIMAL PLACE THAN IS PRESENT IN THE ORIGINAL SET OF VALUES


MEAN OF A FREQUENCY DISTRIBUTION:
xbar = E(f*x)/Ef 
FIRST MULTIPLY EACH FREQUENCY AND CLASS MIDPOINT, THEN ADD THE PRODUCTS / SUM OF FREQUENCIES


WEIGHTED MEAN:
xbar = e(w*x)/Ew 
FIRST MULITPLY EACH WEIGHT AND THE CORRESPONDING VALUE, THEN ADD THE PRODUCTS / SUM OF THE WEIGHTS


A distribution of data is _____ if it is not symmetric and extends more to one side than the other.

SKEWED


A distribution of data is _____ if the left half of its histogram is roughly a mirror of its right half.)

SYMMETRIC


Data _____ (also called negatively skewed) have a longer left tail and the mean and median are to the left of the mode.

SKEWED TO THE LEFT


Data _____ (also called positively skewed) have a longer right tail, and the mean and median are to the right of the mode.

SKEWED TO THE RIGHT


The _____ of a set of data is the difference between the maximum value and the minimum value.

RANGE


The _____ of a set of sample values is a measure of variation of values about the mean.

STANDARD DEVIATION


Step 1: Compute the mean "xbar"
Step 2: Subtract the mean from each individual value to get a list of deviations in the form (x"xbar") Step 3: Square each of the differences obtained from Step 2. This produces numbers of the form (x"xbar")2 Step 4: Add all of the squares obtained from Step 3. This is the value of E(x"xbar")2 Step 5: Divide the total from Step 4 by the number (n1), which is 1 less than the total number of values present. Step 6: Find the square root of the result of Step 5. 
STANDARD DEVIATION


Difference between the standard deviation of a sample and a population.

INSTEAD OF DIVIDING BY N1, DIVIDE BY THE POPULATION SIZE N.


The _____ variance of a set of values is a measure of variation equal to the square of the standard deviation.

VARIANCE


NOTATION: Sample standard deviation

s


NOTATION: Sample variance

s2
