summer math vocabulary Flashcards
what is statistics?
the study of variability
what is variability?
how things differ
what are the 2 branches of stats?
inferential and descriptive
what are descriptive stats?
describing the data that you collected
what are inferential stats?
look at your data and use that to say stuff about the big picture
compare descriptive and inferential stats
descriptive explains the data that you have, inference uses that data you have to try and say something about an entire population
what is data?
any collected information, generally each little measurement
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
compare population to sample
samples are small sets of data of an entire population
compare data to statistics
data is each little bit of information collected from the subjects, statistics are when we summarize them
compare data to parameters
data is each little bit of information collected from the subjects, parameters are the numbers that summarize an entire population
what is a parameter?
a numerical summary 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?
a sample of the entire population
does a census make sense?
it is OK for small populations
difference between a parameter and a statistic
parameters come from populations and statistics come from 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 (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
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
difference between a sample and a census
a sample gives you data from a small portion of the population, whereas a census gives you data from the entire population
