last min. Flashcards
(26 cards)
interpret confidence interval
We are __% confident that the interval from __ to __ captures the amount of ___ (parameter).
interpret confidence level
If we were to select many random samples of the same size from the same population and construct a __% confidence interval using each sample, about __% of the intervals found would capture the amount of ___(parameter).
margin of error decreases with
a greater confidence level and/or greater sample size
interval or tests with z have large counts
greater than 10
interval or tests with t have large counts
greater than 30
Chi-square tests are
goodness of fit, independence, homogeinity
Test for slope conditions are
LINER - Linear, 10%, normal (n >30), equal SD (residual plot shows equal scatter), random
SOCS
shape, outliers, center, spread
If mean is greater than median, the distribution is
right skewed
if the mean is less than the median then distribution is
left skewed
To describe two quantitive variables, describe with
form, direction, strenght, and outliers
correlation tells you
strenght and direction of linear relationship
To find IQR
q3 - q1
To find lower and upper bound
Q1 - 1.5 x IQR, Q3 +1.5 x IQR
For center and spread with symmetric data, use…
mean and sd
For center and spread with skewed data, use…
median with iqr
Percentile is a
point in the data set
Regression line models relationship between
two variables, predicts y based on explanatory variable x
Chance of independent events both happening is
the probability of both multiplied
Z score tells you
how many SD’s a value is away from the mean
Type one error is when
null hypothesis is rejected when it is actually true
Type two error is when
we fail to reject the null when the alternate is actually true
Power is the
chance of detecting a real effect
to find sd of proportion
square root of p(1-p) over n
