# MGSC Exam 1

Studied by 2 people
0.0(0)
get a hint
hint

statistics

1 / 110

### There's no tags or description

Looks like no one added any tags here yet for you.

### 111 Terms

1

statistics

the science of using an assortment of methods to systematically collect, organize, summarize, analyze, and interpret information

New cards
2

descriptive statistics

tabular, graphical, or numerical summaries of data for a particular group

New cards
3

statistical inference

using data collected from a sample in order to make estimates and test hypotheses about the characteristics of a larger inference

New cards
4

population

the set of all elements of interest in a particular study

New cards
5

census

collecting data for the entire population

New cards
6

sample

subset of the population

New cards
7

sample survey

collecting data for a sample

New cards
8

data

information that we collect and analyze

New cards
9

data set

all of the data that is collected for a study

New cards
10

elements

the subjects of a study; entities on which data is collected

New cards
11

variable

attribute of the subjects/elements we are interested in studying

New cards
12

observation

set of all measurements collected for one subject/element

New cards
13

total data values

elements x variables

New cards
14

measurement scale

the nature of the values that are assigned to variables

New cards
15

nominal

categorical variables; does not indicate ranking (ex. gender, zip code)

New cards
16

ordinal

ranked data; distance between not equal/known (ex. socioeconomic class, TRACE scale)

New cards
17

interval

always numeric; distance between integers are equal; no absolute zero (0 doesn’t mean “absence of”) (ex. temperature, dress size)

New cards
18

ratio

lowest value is always zero; has an absolute zero (0 means “absence of”) (ex. age)

New cards
19

qualitative

nominal or ordinal; use words (or rank number) to describe subjects/elements

New cards
20

quantitative

interval or ratio; use numbers to describe subjects/elements

New cards
21

continuous

variables can take on values between whole numbers (fractions/decimals)

New cards
22

discrete

usually only take on whole number values (except shoe size)

New cards
23

experiment

a variable is specifically manipulated by the researcher

New cards
24

constant

a characteristic of elements/subjects that does not vary from one subject to the next

New cards
25

control variable

held constant in a research study by observing only one of its levels

New cards
26

observational research

levels of independent variable already exist (ex. gender, age); cannot make causal statements; looks for relationships between some set of variables

New cards
27

cross-sectional studies

provide a “snapshot” of different groups at one point in time

New cards
28

time series studies

longitudinal; use data that are collected on the same subjects/elements over several points in time; observe changes over time

New cards
29

effects

changes in data patterns

New cards
30

cyclical effect

any usual/consistent variation in daily, weekly, monthly, or annual data not related to change in season

New cards
31

seasonal effect

change in data that can be explained by/attributed to annual calendar-related events

New cards
32

irregular effect

any change in the data is not related to a regular cycle or season; caused by unusual events

New cards
33

the use of data, tehcnology and statistical analysis to answer questions

New cards
34

descriptive analytics

use of data to understand past and current business performance

New cards
35

predictive analytics

use of historical data to identify patterns or relationships and to make predictions about what will happen in the future

New cards
36

prescriptive analytics

identify the best alternatives to minimize or maximize some objective

New cards
37

parameters

greek symbols representing descriptive measure of a population

New cards
38

sample statistics

roman letters representing descriptive measures of a sample

New cards
39

random sample

each member of population has an equal and independent chance of being included in the sample

New cards
40

sampling bias

when a sample is collected in a way that results in some members of the population being more or less likely to be included than others

New cards
41

raw data

data that has not been organized or summarized in any way

New cards
42

frequency distribution

the list of all frequencies for all categoreis

New cards
43

relative frequency distribution

the proportion of the observations that belong to a category f/n

New cards
44

percent frequency distribution

the percent of the observations that belong to a category f/n x 100

New cards
45

class intervals

data divided into sets with equal widths

New cards
46

class midpoint

the value half way between the upper and lower limit of an interval

New cards
47

cumulative frequency distribution

total number of items that have values less than or equal to the upper limit of each class

New cards
48

data vizualization

the process of displaying data meaningully in order to improve decision-making

New cards
49

dashboard

New cards
50

line charts

display data over time

New cards
51

pie chart

used to display relative frequency or percentage distributions

New cards
52

bar chart

used to visually present qualitative data; separated bars

New cards
53

histograms

display frequency distributions of quantitative variables; no spaces between bars

New cards
54

frequency polygon

points used to depict frequency for each class interval

New cards
55

scatter plot

displays relationship between two quantitative variables

New cards
56

trendline

depicts general direction of the relationship between variables

New cards
57

positive relationship

as x increases, y increases

New cards
58

negative relationship

as x increases, y decreases

New cards
59

symmetrical distribution

similar on both sides

New cards
60

negatively skewed distribution

skewed left; most data fall at upper end

New cards
61

positively skewed distribution

skewed right; most data fall at lower end

New cards
62

skewness

the measure of the symmetry of a data distribution

New cards
63

kurtosis

the measure of how peaked or flat a data distribution is relative to a normal distribution

New cards
64

excess kurtosis

kurtosis - 3

New cards
65

mesokurtic

kurtosis = 3, excess = 0

New cards
66

leptokurtic

kurtosis > 3, excess > 0

New cards
67

platykurtic

kurtosis < 3, excess <0

New cards
68

mildly skewed rule of thumb

skewness between -.5 and +.5

New cards
69

moderately skewed rule of thumb

skewness between -.5 and -1 or between +.5 and =1

New cards
70

highly skewed rule of thumb

skewness less than -1 or greater than +1

New cards
71

standard error calculation

plus or minus 3 times the standard error of skewness

New cards
72

mode

value with highest frequency of occurance; unaffected by outliers

New cards
73

median

the middlemost value when arranged in ascending order; not affected by outliers

New cards
74

median index

(n+1)/2

New cards
75

mean

best measure for normal data; can be pulled in direction of outliers

New cards
76

positive skew central tendencies

mode < Median < mean

New cards
77

negative skew central tendencies

mean < median < mode

New cards
78

mean of the means

if groups are the same size use ___

New cards
79

weighted mean

used to calculate the mean of two or more groups when their sample sizes are not equal

New cards
80

percentiles

divide rank-ordered data into 100 equal parts

New cards
81

quartiles

divide rank-ordered data into 4 equal parts

New cards
82

measures of variability

describe the spread of the data around the center

New cards
83

range

largest value - smallest value; sensitive to outliers

New cards
84

Interquartile Range

Q3-Q1; middle half of data

New cards
85

box and whisker plot

shows the center, the spread, and outliers of a data distribution

New cards
86

five number summary

smallest value(within inner fences), Q1, Q2, Q3, largest value(within inner fences)

New cards
87

inner fences

Q1 - (1.5 x IQR) Q3 + (1.5 x IQR)

New cards
88

outer fences

Q1 - (3 x IQR) Q3 + (3 x IQR)

New cards
89

middle 50% of data positively skewed

if median in box is on the left side; the ___

New cards
90

outer 50% of data positively skewed

if longest whisker is to the right of the box; the ___

New cards
91

deviation score

the distance from any score in teh data to the mean of the distribution

New cards
92

zero

deviation scores add up to ___

New cards
93

sum of squares

sum of squared deviation scores ; total variation in the data set

New cards
94

population variance

sum of squares divided by N; average variability

New cards
95

sample variance

sum of squares divided by n-1; average variability

New cards
96

standard deviation

square root of variance; average deviation around the mean of a distribution

New cards
97

degrees of freedom

the number of scores that are free to vary

New cards
98

empirical rule

applies to normal data; 68% between 1 standard deviation, 95% between 2 standard deviation, 99.7% between 3 standard deviation

New cards
99

chebyshev’s theorem

any data set (skewed); what percentage of data lie within k standard deviations of the mean (k>1)

New cards
100

coefficient of variation

how large the standard deviation is relative to the mean

New cards

## Explore top notes

Note
Studied by 172 people
Updated ... ago
5.0 Stars(2)
Note
Studied by 6 people
Updated ... ago
5.0 Stars(1)
Note
Studied by 5 people
Updated ... ago
5.0 Stars(1)
Note
Studied by 116 people
Updated ... ago
5.0 Stars(2)
Note
Studied by 9 people
Updated ... ago
5.0 Stars(1)
Note
Studied by 178 people
Updated ... ago
5.0 Stars(2)
Note
Studied by 7 people
Updated ... ago
5.0 Stars(1)
Note
Studied by 2627 people
Updated ... ago
5.0 Stars(3)

## Explore top flashcards

Flashcard26 terms
Studied by 10 people
Updated ... ago
5.0 Stars(3)
Flashcard22 terms
Studied by 4 people
Updated ... ago
5.0 Stars(2)
Flashcard61 terms
Studied by 4 people
Updated ... ago
5.0 Stars(1)
Flashcard95 terms
Studied by 63 people
Updated ... ago
5.0 Stars(2)
Flashcard40 terms
Studied by 4 people
Updated ... ago
4.0 Stars(1)
Flashcard45 terms
Studied by 7 people
Updated ... ago
5.0 Stars(1)
Flashcard20 terms
Studied by 22 people
Updated ... ago
5.0 Stars(2)
Flashcard76 terms
Studied by 29 people
Updated ... ago
5.0 Stars(2)