Summer Vocab Flashcards
(42 cards)
What is statistics
The study of variability
What is variability
Differences..how things differ. There is variability everywhere.. we all look different, act, prefer.. statisticians look at these differences
What are the 2 branches of AP stats
Inferential and discriptive
What are descriptive stats
Tell and describe the data collected, pics, summaries like mean, median, range etc
What are inferential stats
Look at your data, and use that to say stuff about the BIG PICTURE… like tasting
soup, a little taste tells you about the whole pot… a little sample can tell you a lot
about the big pot of soup (the population).
Compare Descriptive and Inferential
STATS
Descriptive explains the data that you have, inference uses that data you have to
try to say something about an entire population.
What is data?
Any collected information
What is a population?
the group you’re interested in.
What is a sample?
A subset of a population, often taken to make inferences about the population.
We calculate statistics from samples.
compare population to sample
populations are generally large, and samples are small subsets of these
population. We take samples to make inferences about populations. We use
statistics to estimate parameters.
Compare data to statistics
Data is each little bit of information collected from the subjects…. They are the
INDIVIDUAL little things we collect… Statistics are when we summarize them by,
for example, finding the mean of a group of data. If it is a sample, then we call
that mean a “statistic” if we have data from each member of population, then
that mean is called a “parameter”
Compare data to parameters
Data is each little bit of information collected from the subjects, they are the
INDIVIDUAL little things we collect…parameters are the numbers that summarize
an entire population
What is a parameter?
A numerical summary of a population. Like a mean, median, range of a
population
What is a statistic?
A numerical summary of a sample.
We are curious about the average wait time at a Dunkin Donuts drive through in your neighborhood. You randomly sample cars one afternoon and find the average wait time is 3.2 minutes. What is the population parameter? What is the statistic? What is the parameter of interest? What is the data?
The parameter is the true average wait time at that Dunkin Donuts. This is a
number you don’t have and will never know. The statistic is “3.2 minutes.” It is the
average of the data you collected. The parameter of interest is the same thing as
the population parameter. In this case, it is the true average wait time of all cars.
The data is the wait time of each individual car, so that would be like “3.8 min, 2.2
min, .8 min, 3 min”. You take that data and find the average, that average is called
a “statistic,” and you use that to make an inference about the true parameter.
Compare DATA-STATISTIC-PARAMETER using categorical
example
Data are individual measures… like meal preference: “taco, taco, pasta, taco,
burger, burger, taco”… Statistics and Parameters are summaries. A statistic would
be “42% of sample preferred tacos” and a parameter would be “42% of
population preferred tacos.”
Compare DATA-STATISTIC-PARAMETER
using quantitative
example
Data are individual measures, like how long a person can hold their breath: “45
sec, 64 sec, 32 sec, 68 sec.” That is the raw data. Statistics and parameters are
summaries like “the average breath holding time in the sample was 52.4 seconds”
and a parameter would be “the average breath holding time in the population
was 52.4 seconds”
What is a census?
Like a sample of the entire population, you get information from every member of
the population
Does a census make sense?
A census is ok for small populations (like Mr. Nystrom’s students) but impossible if
you want to survey “all US teens”
What is the difference between a
parameter and a statistic?
BOTH ARE A SINGLE NUMBER SUMMARIZING A LARGER GROUP OF NUMBERS….
But pppp parameters come from pppp populations… sss statistics come from ssss
statistics.
If I take a random sample of 20 hamburgers from FIVE GUYS and count the number of pickles on a bunch of them... and one of them had 9 pickles, then the number 9 from that burger would be called \_\_\_\_?
a datum, or a data value
if I take a random sample 20 hamburgers from FIVE GUYS and count the number of pickles on a bunch of them... and the average number of pickles was 9.5, then 9.5 is considered a \_\_\_\_\_\_\_?
statistic. (t is a summary of a sample.)
If I take a random sample of 20 hamburgers from FIVE GUYS and count the number of pickles on a bunch of them... and I do this because I want to know the true average number of pickles on a burger at FIVE GUYS, the true average number of pickles is considered a \_\_\_\_\_\_?
parameter, a one number summary of the population. The truth. AKA the
parameter of interest.
What is the difference between a
sample and a census?
With a sample, you get information from a small part of the population. In a
census, you get info from the entire population. You can get a parameter from a
census, but only a statistic from a sample.
