Quiz 3- Lecture 3 and Lecture 4 Flashcards
the mean and standard deviation of a data set can be used to calculate a z-score, which measures the distance between a particular observation x and the…
mean, measured in units of standard deviation
a percentile is another measure of relative standing, most often used for…
large data sets
a set of n measurements on the variable x has been arranged from smalles to largest. The pth percentile is the value of x that is…
P% greater than the other measurements and is less than the remaining (100-P)%
the lower quartile,Q1, is the value of x that is greater than ___ of measurements and is less than the remaining___.
25%, 75%
The second quartile is the…
median
the upper quartile, Q3, is the value of x that is ___ greater than rest of measurements and is less than the remaining ____
75%, 25%
the interquartile range(IQR) for a set of measurements is the difference between the
3rd and 1st quartile
box plot can be used to find
outliers
z-scores, percentiles and quartiles, and the The Five-Number Summary and the Box Plot are called
measures of POSITION
lower quartile is
the value of x in position 0.25(n+1)
the upper quartiles is…
the value of x in position 0.75(n+1)
We can use 5 numbers to summarize date…
min, Q1, median, Q3, max
the process by which an observation (measurement) is obtained
experiment
the outcome observed on a single repetition of an experiment
simple event
a collection of simple events
event
two events are _______, if when 1 occurs the other can not, vice versa
mutually exclusive
simple events are ____mutually exclusive
ALL
the set of all simple events is called…
sample space, S
some experiments can be generated in stages and the sample space can be displayed in a…
tree diagram
another way to display simple events (besides tree diagram) is to use…
table of outcomes
probability of event A is…( in words)
a measure of our belief that event A will occur
if you repeat an experiment until you eventually generate entire population , the_____ of event A is defined as the probability of Event A
RELATIVE FREQUENCY
P(A)= ___( when n is the number of times that the experiment was performed but n becomes larger and you’ve generated entire population)
lim as n -> infinity of (frequency/n)
each simple event probability must lie between…
0 and 1
the sum of probabilities for all _____ in S(sample space) equals 1
simple events
The probability of event A is equal to the sum of probabilities of the ______ contained in event A
simple events
note that simple events have ____ probabilities
equal
the probability of an event is the sum of the probabilities of the simple events it contains because simple events are…
mutually exclusive
How to calculate the probability of an event:
1. list all the ________ in the sample space
SIMPLE EVENTS
How to calculate the probability of an event:
2. assign an appropriate____ to each simple event
probability
How to calculate the probability of an event:
3. determine which simple events result in the ____ of interest
event
How to calculate the probability of an event:
4. ____ the probabilities of the simple events that result in the event of interest
SUM
(N= large # of simple events)
Each simple event has a probability of..
1/N
n subscript a is the number of _____ that result in event A
simple events
rule for counting # of simple events
mn rule
when 0.25(n+1) and 0.75(n+1) aren’t integers, the quartiles are found by…
interpolation, using the measurements above and below the calculated position
since not integers, we take the lower quartile to be the value of ____ of the distance between the 2 other measurements
3/4
since not integers, we take upper quartile to be the value of ____ of the distance between the 2 other measurements
1/4
if the Q1 is 2.75 then look at the 2nd ordered measurement and the 3rd
lalalalal
