Exam 1

Question 1

what is the formula for union probability?

Answer 1

P(A or B)=P(A)+ P(B)-P(A and B)

Question 2

what is the formula for complement probability?

Answer 2

P(A^C)=1-P(A)

P(A^C)=complement of A

Question 3

what is the conditional probability rule

Answer 3

P(A and B)/P(B)

Question 4

what does sensitivity mean?

Answer 4

true positive and have disease; yes yes

Question 5

what does specificity mean?

Answer 5

true negative and do not have disease; no no

Question 6

what is the parameters for binomial distribution?

Answer 6

X(squiggly line)Bin(n= ,p= )

Question 7

what is the parameters for normal distribution?

Answer 7

X(squiggly line)N(mean= , std. dev.= )

Question 8

what are the appropriate graphs for quantitative (discrete or continuous) data?

Answer 8

histograms, box plots, or dot plots

Question 9

what are the appropriate graphs for categorical data?

Answer 9

pie chart, Pareto chart, or bar chart

Question 10

explain SOCS

Answer 10

Shape-skewness, modality
Outliers-how many, high/low
Center-depends on skewness and outliers, mean or median
Spread-depends on skewness and outliers, std. dev. or IQR

Question 11

what signifies a strong correlation?

Answer 11

.7+

Question 12

what signifies a moderate correlation?

Answer 12

.4-.6

Question 13

what signifies a weak correlation?

Answer 13

.1-.3

Question 14

examples of variability in the real world (3)

Answer 14

gas prices, heights, temperatures

Question 15

what are the 3 main reasons to study statistics?

Answer 15

-being informed
-making good decisions
-evaluating those decisions

Question 16

where do we find statistics? (4)

Answer 16

news, articles, surveys, charts/graphs

Question 17

in statistics, ____________ provides meaning to our studies

Answer 17

context

Question 18

what are the 2 ways stats differs from math?

Answer 18

role of context and logic of statistical inference

Question 19

the total set of all “individuals” of interest

Answer 19

population

Question 20

a subset of “individuals” selected from the population

Answer 20

sample

Question 21

numerical characteristic of a population, a fixed quantity; one, set value(typically unknown)

Answer 21

parameter

Question 22

numerical characteristic of a sample, a variable quantity; every new sample creates a new _____________

Answer 22

statistic

Question 23

match these:

population sample
statistic parameter

Answer 23

population–>parameter
sample–>statistic

Question 24

what 3 things should you be able to identify in a statistical question?

Answer 24

-the population being studied
-the variable(characteristic) to be measured
-the variation that may occur in the measurement of that characteristic

Question 25

what are the 4 steps in solving a statistical problem?

Answer 25

-formulate a statistical question -collect data -analyze data -interpret and communicate results

Question 26

methods for organizing data; summaries, reports, records

Answer 26

descriptive statistics

Question 27

methods for drawing conclusions about a population; predict, estimate, conclude, infer

Answer 27

inferential statistics

Question 28

a list of distinct categories and their counts

Answer 28

frequency distribution

Question 29

a list of distinct values and their relative frequencies (proportions/percentages)

Answer 29

relative frequency distribution

Question 30

how is relative frequency found?

Answer 30

taking the frequency for that category and dividing it by the sample size

Question 31

what are the 2 numerical summaries for categorical data?

Answer 31

frequency distribution and relative frequency distribution

Question 32

what methods are used to describe quantitative data? (3)

Answer 32

SOCS, scatterplot, contingency table

Question 33

what is the law of large numbers?

Answer 33

the probability of an event is the proportion of times it occurs in a large number of repetitions of the experiment the more times we do an experiment, the closer our experimental probability will become to our theoretical probability

Question 34

probability based on personal opinion

Answer 34

subjective probability

Question 35

probability based on formulas

Answer 35

theoretical probability

Question 36

probability based on results of a random experiment

Answer 36

experimental probability

Question 37

events that have no outcomes in common

Answer 37

mutually exclusive

Question 38

the occurrence of one event has no effect on the other event

Answer 38

independent

Question 39

individual event probability

Answer 39

marginal probability

Question 40

probability of the overall sample

Answer 40

unconditional probability

Question 41

probability that's conditioning on an event

Answer 41

conditional probability

Question 42

how do you verify if something is a valid probability distribution?

Answer 42

add up all probabilities and verify that they equal 1 exactly

Question 43

what are the 4 binomial conditions?

Answer 43

1) fixed # of trials, n= 2) 2 possible outcomes, success/fail 3) probability of success is the same? p= 4) independent