exam 1

Question 1

how do you calculate z score

Answer 1

(value of int - mean) / SD

Question 2

what are the types of variables?

Answer 2

Catagorial, Numerical, Nominal, Ordinal, Discrete, Continuous

Question 3

what is a nominal variable?

Answer 3

Defined catagory with no specific order

Question 4

Example of a nominal variable

Answer 4

Marital status, Political party, eye color

Question 5

what is a ordinal variable

Answer 5

ordered catagories

Question 6

ordinal variable examPLE

Answer 6

Freshman, sophmore, junior, senior

Question 6

Population (N)

Answer 6

Contains all of the items or indivuduals of interest that you seek to study

Question 7

Sample (n)

Answer 7

Contains only a portion of a population interest

Question 8

Population parameter

Answer 8

summarizes the value of a specific variable for a population

Question 9

sample statistic

Answer 9

summarizes the value of a specific variable for sample data

Question 10

Probability sample

Answer 10

items in the
sample are chosen on the basis of known
probabilities.

Question 11

which are probability samples

Answer 11

simple random, stratified, cluster, systematic

Question 12

What type of samples are non probability

Answer 12

Judgement, Convenience

Question 13

Simple random sample

Answer 13

Participants are randomly selected from a population

Question 14

systematic

Answer 14

Method for selecting sample from a population in a randomized manner to minimize sampling error

Question 15

Stratified sample

Answer 15

Divides population into two or more subgroups according to some common characteristics. A sample is taken from each group and is combined into one

Question 16

Cluster sample

Answer 16

Population is divided into several clusters, each representing the population

Question 17

Benefit of using Radom sample and systematic sample

Answer 17

simple to use

Question 18

benefit of stratified sample

Answer 18

ensures respresentation of individuals across the entire population

Question 19

cluster sample

Answer 19

more cost effective

Question 20

convince sampling

Answer 20

individuals are selected based on only the fact that they are easy, inexpensive or convinent

Question 21

Judgement sample

Answer 21

you get opinions of preselected experts in the subject matter

Question 22

Coverage error or selection bias

Answer 22

exists if some group are excluded from the frame and have no change of being selected

Question 23

nonresponse or bias error

Answer 23

people who do respond may be different from those who don’t respond

Question 24

sampling error

Answer 24

variation from sample to sample will always exist

Question 25

measurement error

Answer 25

due to weakness in question design and / or respondent error

Question 26

How is the Pareto chart organized?

Answer 26

The "Vital Few" (most influential) are the first on the X axis

Question 27

what is the stem and leaf display

Answer 27

organized data into groups (Stems) so that the values within each group (Leaves) can branch out to the right on each row

Question 28

what is the geometric mean

Answer 28

Rate of change of a variable over time

Question 29

what does the measure of variation give

Answer 29

Information on the spread of variability or dispersion of the data values

Question 30

what is the rule of thumb for z score

Answer 30

Greater then 3 or less then -3 are outliers

Question 31

what is the five number summary

Answer 31

the 5 numbers that help describe the center, spread and shape of data

Question 32

what is included in the 5 number summary

Answer 32

Min, Q1, Median, Q3, Max

Question 33

Left skewed

Answer 33

Mean< Median

Question 34

Symmetric

Answer 34

Mean = Median

Question 35

Right-Skewed

Answer 35

Median < Mean

Question 36

Empiracle rule

Answer 36

approximates the variation of data in a symmetric bell distributin

Question 37

In the empriacle rule how much of the data is within 1 standard deviation of the mean

Answer 37

68%

Question 38

In the empriacle rule how much of the data lies within 2 standard deviations of the mean

Answer 38

95%

Question 39

In the empriacle rule how much of the date lies within three standard deviations of the mean

Answer 39

99.7%

Question 40

When do you use chebyshevs rule

Answer 40

to find the values that fall within k of the mean

Question 41

Cov(x,y)>0

Answer 41

X and Y move in the same direction

Question 42

Cov(x,y) < 0

Answer 42

X and Y move in opposite directions

Question 43

Cov(x,y) = 0

Answer 43

X and Y are independent

Question 44

Can you determine the strength of relationship from COV

Answer 44

No

Question 45

coeffienct of correlation

Answer 45

measures the relative strength of the linear relationship between two numerical variables

Question 46

Priori probability

Answer 46

Based on prior knowledge of the process

Question 47

Empiracle probability

Answer 47

Based on specific date

Question 48

Subjective probability

Answer 48

Based on a combination of general date, personal opinion, and analysis of a particular situation

Question 49

Continuous

Answer 49

Measurment

Question 50

Discrete

Answer 50

Counting (EX: number of students)

Question 51

What is a distinct clue it is Pareto

Answer 51

WIll say "Trival Many" and is catagorial

Question 52

when is the only time you can use empiracle rule

Answer 52

If data is bell shaped

Question 53

Subjective

Answer 53

Analysis of a subject