module 1 intro

Question 1

levels of measurement

Answer 1

categorical and scale

Question 2

sometimes referred to as discreet data, where numbers are used to represent categories of information, qualitative in nature. the types are nominal and ordinal data

Answer 2

categorical data

Question 3

a numerical measurement of something in which the difference between values has meaning. quantitative in nature. referred to as continuous data. two types are interval and ratio

Answer 3

scale

Question 4

data that is grouped in unordered categories. only label holds value. number assigned is meaningless. can be binary or non binary

eg binary yes or no non binary blue eye green eyes brown eyes hazel eyes

Answer 4

nominal

Question 5

data that is grouped in ordered categories, the number assigned to the category means something. calculations cannot be performed on. these numbers. referred to as ranked data

eg disagree somewhat disagree neutral somewhat agree

Answer 5

ordinal

Question 6

a numerical measurement on a scale where each point is placed at an equal distance from one another. there is no true zero

eg temperature, 0 degrees doesn’t mean absence of heat

Answer 6

interval

Question 7

measurement of something where the numbers are not restricted to certain values and there is a true zero

eg amount of money in pocket 0 = no money

Answer 7

ratio

Question 8

true or false nominal data has no inherent order or ranking

Answer 8

true

Question 9

true or false interval data has equal spacing between values but no true zero

Answer 9

false

Question 10

true or false ordinal data can tell you how much more one value is than another

Answer 10

false

Question 11

true or false ratio data can be used to calculate meaningful ratios example twice as much

Answer 11

true

Question 12

identify the level of measurement

type of pet

Answer 12

nominal

Question 13

star rating at restaurant 1-5

Answer 13

ordinal

Question 14

temperature in celsius

Answer 14

interval, equal intervals but no true zero, 0 doesn’t mean absence of heat

Question 15

age in years

Answer 15

ratio

Question 16

time of day in a clock

Answer 16

interval, no true zero

Question 17

exam scores as percentages

Answer 17

ratio, percent scores have a true zero 0% =0 no points

Question 18

happiness level rated as unhappy neutral happy

Answer 18

ordinal

Question 19

relative frequency =

Answer 19

absolute frequency/ sum of all frequencies

Question 20

measures of central tendency

Answer 20

mean median and mode

Question 21

the sum of all values divided by the number of values in the data set. denotes as x bar. also known as average

Answer 21

mean

Question 22

most sensitive to outliers

Answer 22

mean

Question 23

best measure of central tendency for nominal data

Answer 23

mode

Question 24

best measure of central tendency for ordinal data

Answer 24

median or mean depending on category

Question 25

best measure of central tendency for scale data

Answer 25

mean median or mode

Question 26

the variability of a set of data is also referred to as ___

Answer 26

spread

Question 27

two common ways of describing the spread of data

Answer 27

range and interquartile range (IQR)

Question 28

range

Answer 28

a way of measuring the spread of data by describing the difference between the minimum and the maximum value in a data set. range = maximum value - minimum value

Question 29

interquartile range

Answer 29

a way of measuring the spread of data by dividing the data set into quartile as. by finding the quartiles l you can identify the range of values that way within 50% of the median of a data set.

Question 30

how to calculate interquartile range

Answer 30

order data calculate median calculate median of lower half upper half findings are IQR= Q3-Q1

Question 31

the larger the IQR value the ____

Answer 31

more spread out the data is

Question 32

how to calculate variance

Answer 32

identify the distance between each data point and the mean and then averaging those distances (subtract the mean from each value)

Question 33

degrees of freedom

Answer 33

the number of values free to vary in a data set, total observations minus 1 n - 1

Question 34

standard deviation

Answer 34

a way to calculate variance around the mean. calculated by taking a positive square root of variance or s2. when you take the positive square root of something that is swuared it cancels out the square

Question 35

how do you calculate standard deviation

Answer 35

it’s just square rooted variance squared

Question 36

what does a high standard deviation indicate?

Answer 36

the data points are more spread out from the mean, a high sd means more variability data is more spread out

Question 37

true or false if all the data points in the set are the same the sd cannot be calculated

Answer 37

false, there is is no spread if the data is the same, no spread so sd is 0

Question 38

a small standard deviation means the data values are clustered closely around the mean true or false

Answer 38

true

Question 39

absolute number

Answer 39

the raw numbers collected during the days acquisition process

Question 40

relative number

Answer 40

the absolute numbers shown as a proportion or percentage

Question 41

true or false variance is measured in the same unit as the original data

Answer 41

false, variance is in squared units not the same as data

Question 42

true or false the standard deviation can be negative

Answer 42

false, it is always zero or positive never negative

Question 43

true ir false SD is a measure of central tendency

Answer 43

false, it is a measure of spread

Question 44

why might a public researcher want to look at standard deviation in a survey response?

Answer 44

to understand how much variation or spread there is in the response. even if the mean is the same between two groups, the sd tells them how consistent or inconsistent people’s answers are.

Question 45

if two datasets have the same mean but different standard deviations what does that tell you

Answer 45

it tells you that one dataset is more spread out than the other, even though they centre around the same average. the data set with the larger Sd has more variability meaning individual data points tend to deviate more from the mean. the dataset with the smaller sd is more consistent and tightly clustered around the mean true

Question 46

the

Answer 46

it tells you that one dataset is more spread out than the other, even though they centre around the same average. the data set with the larger Sd has more variability meaning individual data points tend to deviate more from the mean. the dataset with the smaller sd is more consistent and tightly clustered around the mean

Question 47

a small sd means and large sd means what

Answer 47

small sd means people gsve very similar answers and large means people have a wide range of answers

Question 48

why is SD important in real life

Answer 48

low sd means most people consistently liked it high sd means some people loved it and some people hated it. can influence deductions such as as why there is so mu fb variability

Question 50

to avoid having values canceled out when using variance on symmetrical data, use

Answer 50

variance squared. (s2) makes all values positive so they don’t cancel each other out