U nit 5 Practice Test
M ULTIPLE CH OICE. Choose the one alternative that best completes the statement or answers the question.
1) W e ha ve calculate d a 95% confidence interval an d w ould prefer for our next confidence interval to
ha ve a sm aller m arg
Chapter 13: Experiments and Observational Studies
Observational studies
observational studies  researchers don't assign choices, they observe them
retrospective study  subjects are selected and then their previous choices/
behaviors are studied
can
Class Notes
Probability
"And" means multiply
"Or" means add
"Not" means 1 minus %
Chapter 14: From Randomness to Probability
Random phenomenon  a phenomenon is random if we know what outcomes could
happen, but not which particular values will happen
Class Notes
Used when events are not disjoint => center of the venn diagram
false negative  you're okay but you're sick
ex. girl seems okay but she's crazy
false positive  wrong but you're bad
ex. turned girl down, but she would have been a good da
Chapter 16: Random Variables
random variable  a random variable assumes any of several different numeric values
as a result of some random event. random variables are denoted by a capital letter
such a X
discrete random variable  a random variable th
Chapter 18: Sampling Distribution Models
sampling distribution model  different random samples give different values for a
statistic. The sampling distribution model shows the behavior of the statistic over
all the possible samples for the same size n.
Chapter 17: Probability Models
Bernoulli trials, if.
there are two possible outcomes
the probability of success is constant
the trials are independent
Geometric probability model  is appropriate for a random variable that counts the
number of Bernou
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Chapter 19: Confidence Intervals for Proportions
Standard Error  when we estimate the standard deviation of a sampling distribution
using statistics found from the data, the estimate is called a standard error.
Confidence Interval  a level C confidenc
Means Testing
Ttest => hypothesis test
confidence interval
no phat; now ybar
no p; now u
no more z but t
no normalcdf, but tcdf
dF  degrees of freedom (n  1)
check conditions and assumptions
must be random, independent, 10%
nearly normal n
Chapter 20: Testing Hypotheses About Proportions
Null Hypothesis  the claim being assessed in a hypothesis test. Usually, the null
hypothesis is a statement of "no change from the traditional value," "no effect," "no
difference," or "no relationship." F
Categorical Data
Chi Square tests
three types
goodness of fit => distribution is as expected (ex. dice, hockey players births)
homogeneity test => 1 variable (ex. eye color) with two groups (ex. men,
women)
independence test => 2 variables with more
Chapter 4: Displaying and Summarizing Quantitative Data
Histograms
displays the distribution at a glance
data is sliced up into bins (at least 5) => provide the building blocks for the
histogram
there are no spaces in between the bars; if there are, t
Chapter 7: Scatterplots, Associations, and Correlation
Scatterplots
allow you to see patterns, trends, relationships, and even the extraordinary
value sitting apart from the others
shows relationship between two quantitative variables
ask about associ
Chapter 5: Understanding and Comparing Distributions
Boxplots and 5number summaries
Draw a vertical axis spanning the extent of the data. Then draw boxes based on
the lower and upper quartiles and the median (then connect them to form a box)
place the
Chapter 6: The Standard Deviation as the Ruler and the Normal Model
The standard deviation as a ruler
trick in comparing different looking values is to use standard deviations
measure the amount of standard deviations something is from the mean
Standa
Class Notes (9/10)
Types of data
Categorical (qualitative)  a quality (ex. shoe size, phone numbers)
quantitative  a number (ex. assigning numbers to men and women)
marginal distribution  ex. on page 24 and 25
Chapter 3: Displaying and Describing C
Class Notes
Reexpressing data
skewed right  usually take the log of the data
skewed left  square the yaxis
try log first, then square root, the inverses and stuff
only do this to the yaxis
once you reexpress the data, recheck the residuals be
Chapter 9: Regression Wisdom
Getting the "bends": When the residuals aren't straight
always good to check the scatterplot of the residuals for bends that may have
been overlooked in the original scatterplot
Sifting residuals for groups
whenever we sus
Class notes (8/26)
Survey leads to an inference => you can't ask everyone
problems with surveys:
error  these can't be helped; normal => gun target: high, low, left, right
bias  very bad; try to eliminate => bent gun sight
response bias  feel comp
Chapter 11: Understanding Randomness
The best ways we know to generate data that give a fair and accurate picture of the
world rely on randomness, and the ways in which we draw conclusions from those
data depend on the randomness
Simulation
Building a
Class Notes
you cannot go backwards on the linear model equations (ex. you can solve for fat
with a given amount of protein, but you can't solve for protein with a given fat
amount)
r^2 = x% => x% of yvalue can be explained by variations of the xvalue
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Ecology The study of how organisms interact with each other and their enviornment
Climate The longterm prevailing weather conditions at a given pl
LITTORAL ZONE (LAKE)
NERITIC ZONE (OCEAN) WHERE THE SUN TOUCHES
THE GROUND
OCEANIC ZONE OCEAN
PHOTIC ZONE AUTOTROPHS
PELAGIC ZONE
APHOTIC ZONE NO LIGHT, HETEROTROPHS
LIMNETIC ZONE POND
BE
N
Chapter 10
10.1




Photosynthesis
o occurs in chloroplasts (organelles containing thylakoids)
o 6CO2 + 12H20 + Light Energy C6H1206 + 6O2 +6H20
o Redox process
H2O is oxidized and CO2 is reduced
Chloroplasts
CHAPTER 51
1. Behavior Individually, an action carried out by muscles or glands under control of the nervous
system in response to a stimulus; collectively, the sum of an animals responses to external and
internal sti
When 10 different fish were placed in a temperaturegradient tank and given 30 minutes in the
tank, the observed outcome of this experiment was that most of the fish preferred the medium
temperature between 12oC and