STAT 101
What is the mean and stdev of a standard normal distribution? - ANSMean: 0
Std. Dev: 1
What is true about mean and variance of a Poisson? - ANSthey are equal!
Can two events be disjoint and independent? - ANSNo - they are mutually exclusive
In a Poisson distribution, the time or
the distance between observations has
a (an) _______________distribution - ANSExponential
In a binomial distribution, if np and
n(1-p) are both bigger than 10, then
what is true? - ANSThe distribution is approximately
Normal with mean np and
variance np(1-p)
If every organ in my body has probability of failure = .01 in this decade, and I have 100 organs
in my body, what is the probability that at least one organ fails this decade? -
ANS1-.99^100=1-0.36=0.64
A binomial distribution with n=1 is called a - ANSbernoulli
In a normal distribution with a mean 10 and standard deviation 5, what is the probability of
getting exactly zero? - ANSzero
What are the mean and variance of a chi-square distribution with 8 degrees of freedom? -
ANSMean: 8
Variance: 16
If the probability of sleeping through your alarm each day is 0.1, what are the mean and
variance of the number of times you sleep through your alarm in a 100 day semester? -
ANSMean: 100
Variance: 9
Error/Residual formula - ANS
Formula confidence interval for a single mean - ANSx(bar) +/- [t-score]*[S/sqrt(n)]
Formula for sample variance - ANS
, Equation for multiple regression
(Generalized Linear Model) - ANS
Formula for confidence interval for a single proportion - ANS
Formula for total sum of squares - ANSSum of squares due to Group Means + Sum of Squares
Due to Errors
SST = SSG + SSE
A normal quantile plot of regression residuals should look like... - ANSa line
(indicates residuals are approx. normally distributed)
True or false: predictors with larger regression coefficients are more significant than predictors
with smaller regression coefficients - ANSFALSE
What do you need to do to categorical variables in a regression model? - ANSmake indicator
variables and leave one out
If you have heteroskedasticity you can use _______ to try to find a suitable transformation -
ANSBox-Cox procedure
TRUE OR FALSE: A box-cox procedure will always find a good transformation to fix
heteroskedasticity - ANSFALSE - it only works if the variance is some power function of the
mean
What is assumed about the residuals in regression analysis? - ANSResiduals are normally
distributed with constant variance.
In One-Way ANOVA, what is the best multiple comparison correction for comparing levels to a
pre-defined control group? - ANSDunnett
What is true about the mean and median of a symmetric distribution? - ANSThey are Equal
What is defined as an outlier? - ANSAn observation that is more than 1.5*IQR above the third
quartile
A ______ plot allows you to examine the relationships between a large number of continuous
predictors. - ANSmatrix plot
A list of every possible person or object you might sample is called a - ANSSampling Frame
What is the mean and stdev of a standard normal distribution? - ANSMean: 0
Std. Dev: 1
What is true about mean and variance of a Poisson? - ANSthey are equal!
Can two events be disjoint and independent? - ANSNo - they are mutually exclusive
In a Poisson distribution, the time or
the distance between observations has
a (an) _______________distribution - ANSExponential
In a binomial distribution, if np and
n(1-p) are both bigger than 10, then
what is true? - ANSThe distribution is approximately
Normal with mean np and
variance np(1-p)
If every organ in my body has probability of failure = .01 in this decade, and I have 100 organs
in my body, what is the probability that at least one organ fails this decade? -
ANS1-.99^100=1-0.36=0.64
A binomial distribution with n=1 is called a - ANSbernoulli
In a normal distribution with a mean 10 and standard deviation 5, what is the probability of
getting exactly zero? - ANSzero
What are the mean and variance of a chi-square distribution with 8 degrees of freedom? -
ANSMean: 8
Variance: 16
If the probability of sleeping through your alarm each day is 0.1, what are the mean and
variance of the number of times you sleep through your alarm in a 100 day semester? -
ANSMean: 100
Variance: 9
Error/Residual formula - ANS
Formula confidence interval for a single mean - ANSx(bar) +/- [t-score]*[S/sqrt(n)]
Formula for sample variance - ANS
, Equation for multiple regression
(Generalized Linear Model) - ANS
Formula for confidence interval for a single proportion - ANS
Formula for total sum of squares - ANSSum of squares due to Group Means + Sum of Squares
Due to Errors
SST = SSG + SSE
A normal quantile plot of regression residuals should look like... - ANSa line
(indicates residuals are approx. normally distributed)
True or false: predictors with larger regression coefficients are more significant than predictors
with smaller regression coefficients - ANSFALSE
What do you need to do to categorical variables in a regression model? - ANSmake indicator
variables and leave one out
If you have heteroskedasticity you can use _______ to try to find a suitable transformation -
ANSBox-Cox procedure
TRUE OR FALSE: A box-cox procedure will always find a good transformation to fix
heteroskedasticity - ANSFALSE - it only works if the variance is some power function of the
mean
What is assumed about the residuals in regression analysis? - ANSResiduals are normally
distributed with constant variance.
In One-Way ANOVA, what is the best multiple comparison correction for comparing levels to a
pre-defined control group? - ANSDunnett
What is true about the mean and median of a symmetric distribution? - ANSThey are Equal
What is defined as an outlier? - ANSAn observation that is more than 1.5*IQR above the third
quartile
A ______ plot allows you to examine the relationships between a large number of continuous
predictors. - ANSmatrix plot
A list of every possible person or object you might sample is called a - ANSSampling Frame