Getting Mean
Evaluate the mean of this data set:
1,3,3,5,6,6,6
approx. = 4.2857 or 30/7
equation for mean?
x̄ = (Σxi) / n
what is mean
the average of a data set
during what type of distribution are the mean, median, and mode mostly equal?
symmetric/symmetrical distribution
type of data stored numerically(counted)
Evaluate the mean of this data set:
4,5,7,8,8,10,10,11,20
approx. = 9.222 or 83/9
equation for STDV?
σ=√Σ(x-x̄)2/n-1
what is p-hat
the statistic or sample proportion of a data set
What can be inferred from a p value between 0.05-0.10?
the observed data is unlikely to occur
what is qualitative data
non-numerical information collected through methods like observation
Interpret:
Bob is trying to find the average number of ducks he sees each week during his morning jogs when passing by a lake.
Week one: four ducks Week two: zero ducks
Week three: three ducks Week four: five ducks
Week six: two ducks Week five: zero ducks
What is the mean of this data set and what does it suggest?
approx. = 2
On average, Bob sees 2 ducks every week
equation for p-hat?
z*√p(1-p)/n (p=p-hat)
what is mode
a measure of central tendency(aka what number/s appear the most)
55% of Americans believe they are smarter than the average american while 35% believe they are just as smart as the average American
what is nominal data?
data that is used to label variables without providing any quantitative value
In the 1600s(1635) Henry Gellibrand first utilized the word ¨meane¨ in a mathematical context
equation for margin of error?
z*√p*(1-p)/n
what is a dependent variable
the variable that is being measured
What percent of Americans believe ghosts/demons are real?
45%, so spooky!
what is ordinal data?
a type of qualitative (non-numeric) data that groups variables into descriptive categories
Who was the first man to use the mean as the representative value for an aspect of a population OR when?
The Belgian statistician Quetelet (1796-1874)
equation for z-score?
z = (x-μ)/σ
what is a observational study
observes individuals and measures variables of interest but does not attempt to influence the responses
On average, how much trash does the average american produce a day?
5.91 lbs of waste EVERY DAY
what is interval data?
a type of numerical data characterized by equal distances between values on a scale