AP stats summer Flashcards
learn all vocab
Statistics
the study of variability
Variability
how things differ
2 branches of ap stats
inferential and descriptive
descriptive stats
tell the data you collected using mean, median, mode, range
inferential stats
look at the data and use it for the big picture
data
any collected info
population
the group you are interested in
sample
A subset of a population, often taken to make inferences
about a population.
Compare population to sample.
Populations are generally large and samples are small
subsets of a 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…
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 every member of a
population, then that mean is called a “parameter”
Compare descriptive to inferential
STATS.
Descriptive explains to you about the data that you have,
inference uses the data you have to try to say something
about an entire population.
Compare data to parameters
Data is each little bit of information collected from the
subjects…They are the INDIVIDUAL little things we collect…
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 every member of a
population, then that mean is called a “parameter”
parameter
A numerical summary of a population. Like a mean,
median, range,…of a population
statistic
A numerical summary of a sample. Like a mean, median,
range,…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 each individual car, so that
would be like “3.8min, 2.2min, 0.8min, 3min”. 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 Data
Data are individual measures…like meal preference “taco,
taco, pasta, burger, burger, taco”…Statistics and parameters
are summaries. A statistic would be “42% of the sample
preferred tacos.” A parameter would be “42% of the
population preferred tacos.”
Compare DATA-STATISTIC-PARAMETER using Quantitative Data
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”
census
Like a sample of the entire population, you get info 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
samples.
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.