descriptive statistics lec

Question 1

Observationofonevariablemay be shown visually by putting the variable’s on one axis and putting the frequency on the other.

Answer 1

Visual Presentation of Data

Question 2

A bar graph wherein the number of units observed is on the y-axis (_____) while the measurement levels are on the _____

Answer 2

frequency; x-axis; histogram

Question 3

in histogram the bars are..

Answer 3

The bars are visually proportional to each other.

Question 4

A figure that is shorthanded
presents a histogram.

Answer 4

Frequency Polygon

Question 5

A ___ is placed at the center of the top of the bars and connected to form a polygon. This better ennuncuates the data shape.

Answer 5

dot

Question 6

Basic graphs that can illustrate one or more data sets in one graph.

Answer 6

Line Graph

Question 7

two types of line graph and its difference

Answer 7

-Arithmeticlinegraphs
○ Have both x and y-axes on
an arithmetic scale.
○ Both values are numerical.

● Semi-logarithmic line graph ○ Has the y-axis as a
logarithmic axis

Question 8

Parameters of a Frequency Distribution

Answer 8

central tendency and dispersion

Question 9

Frequencydistributionsfrom continuous data are defined by types of descriptors, known as _____.

Answer 9

parameters

Question 10

● Defined as the value used to represent the center or the middle (average) of a set of data values.
● Locates observations on a measurement scale.

Answer 10

Central Tendency

Question 11

● Describes the spread of values in a given data set.
● Suggests how widely spread out the observations are.

Answer 11

Dispersion

Question 12

dispersion prefers…

Answer 12

Prefers low values, low variance, low standard deviation = not spread out data, results are not far from each other.

Question 13

Measures of Central Tendency

Answer 13

mean, median, mode

Question 14

Average value or the sum (Σ) of all
the observed values (𝑥𝑖) divided

Answer 14

mean

Question 15

has the most mathematical
properties and most representative of the dataset if not for our outliers.

Answer 15

mean

Question 16

The middle observation data when
data has been arranged from ______. When the dataset is an even number (hence no natural middle point), the two middling variables are averaged to find a median.

Answer 16

highest to lowest, median

Question 17

Rarely used to make inferential conclusions from, but is used frequently in-healthcare and economics.

Answer 17

median

Question 18

Most commonly observed value
(the value most frequently
observed).

Answer 18

mode

Question 19

The downside to using the mode

Answer 19

a set of data may have no mode, or it may have more than one mode.

Question 20

Measures of Dispersion

Answer 20

Variance and sd, mean deviation

Question 21

A statistical measurement of the
spread between numbers in a data
set.
● It measures how far each number
in the set is from the mean (average), and thus from every other number in the set.

Answer 21

Variance

Question 22

formula for variance

Answer 22

lamo ne yen

Question 23

sample, degree
offreedom

Answer 23

N-1

Question 24

Average amount of variability in
your dataset.
● It tells you, on average, how far
each value lies from the mean.

Answer 24

Standard Deviation

Question 25

A high standard deviation means

Answer 25

that values are generally far from the mean,

Question 26

low standard deviation means

Answer 26

values are clustered close to the mean.

Question 27

di erence between the observed value of a data point and the expected value is known as deviation in statistics.

Answer 27

Mean Deviation

Question 28

the average deviation of a data point from the mean, median, or mode of the data set.

Answer 28

mean deviation or mean absolute deviation

Question 29

Values that split sorted data or a probability distribution into equal parts.

Answer 29

Quantiles

Question 30

A statistical term that
describes a division of observations into four
defined intervals based on the values of the data and how they compare to the entire set of observations.

Answer 30

Quartiles

Question 31

A type of quantiles, obtained by adopting a subdivision into 100 groups.

Answer 31

Percentiles

Question 32

Calculated by dividing an ordered set of data into 100 equal parts.

Answer 32

percentiles

Question 33

Di erence between the highest and lowest values.
○ Size of the narrowest interval which contains all the data.

Answer 33

range

Question 34

○ Di erence between the
third and the first quartile.
○ Size of the narrowest
interval which contains all the data.

Answer 34

InterquartileRange

Question 35

A measure of the
asymmetry of a
distribution.

Answer 35

skewness

Question 36

A distribution is
asymmetrical when

Answer 36

its left and right side are not mirror images.

Question 37

T/F: A distribution can have right (or positive), left (or negative), or zero skewness.

Answer 37

true

Question 38

other term for skewness

Answer 38

horizontal imbalance

Question 39

A descriptive statistic used to help
measure how data disperse between a distribution’s center and tails, with larger values indicating a data distribution may have “heavy” tails that are thickly concentrated with observations or that are long with extreme observations.

Answer 39

Kurtosis

Question 40

other term for Kurtosis

Answer 40

vertical imbalance

Question 41

Xi means

Answer 41

FOr each individual observation

Question 42

Xi means

Answer 42

Or each individual observation

Question 43

The di erence between the observed value of a data point and the expected value is known as

Answer 43

Deviation

Question 44

Uses boxes and lines to depict the distributions of one or more groups of numeric data.

Answer 44

Box plot

Question 45

indicate the range of the central 50% of the data, with a central line marking the median value.

Answer 45

Box plot