STAT 202: PROBABILITY, ESTIMATION, AND HYPOTHESIS TESTING

STAT 202: PROBABILITY, ESTIMATION, AND HYPOTHESIS
TESTING




T: Can't have two outcomes occur at the same time.

I: Outcomes are independent of one another.

R: There is a constant rate of occurrence. - answers✔✔Poisson distribution properties?



Lambda: intensive / rate of occurrence represents the average rate at which events occur per
unit of time.

Mu: Average number of occurrences in t units of time. - answers✔✔Difference between mu and
lambda?



Always skewed to the right. - answers✔✔What does Poissons distribution look like graphically?



dpois(x,mu)

ppois(x,mu) - answers✔✔Poisson's distribution in R.



Describe the theoretical distributions of data. - answers✔✔What do density curves do?



Always above or on the x-axis, never below. - answers✔✔Where is the density curve located in
relation to the x-axis.



1 - answers✔✔How much is the area under the density curve?

, - answers✔✔What is the probability function of Uniform distribution?



dunif(x,a,b)

punif(x,a,b) - answers✔✔Uniform distribution in R.



- answers✔✔What is the probability function for a Standard Normal distribution?



dnorm(z,mu,sigma)

pnorm(z,mu,sigma)

qnorm(P,mu,sigma) - answers✔✔Standard Normal distribution in R.



X~N(0,1) - answers✔✔What is the notation of Standard Normal distribution?



They divide the data up into 100 bins such that the ith percentile is the point at which i% of the
data is below it. - answers✔✔What do percentiles do?



- answers✔✔Probability function of Normal distribution?



X~N(mu,sigma) - answers✔✔Notation of Normal distribution?



It's symmetric about its mean, such that mean = median. - answers✔✔What is the density
curve symmetric about for a Normal distribution?



dnorm(x,mu,sigma)

pnorm(x,mu,sigma) - answers✔✔Normal distribution in R.