kurtosis not kertosis excel ult 4
determine significance
dividealpha by 2 if two tail
zscore crit times var then divide by sqrt n samp
zscore method
numerator xbar minus mu
denom var divide by sqrt n samp
ttest find sd
xbar minus mu divided by
denom sampsd timessqrtn
if pop mesn used its zscore
convert mormal to zscore is x minus mu then divide by se
t.inv function get t random variable
p value need t distr prob not percent so use t.dist
ttest sample size is small, and the population standard deviation is not known
ztest opposite. differenve is if samp size less than 30
test pop equal var two tail ftest
test alpha with la veen
large f ratio more dif in var
always large var minus small var for fmax
degree freedom samp size minus one
f dist needs two groups only same samp size
always skew right
to find crit value
select ftable alpha then look dof column group size rows. if larger reject null
var not equal confidence interval not one
f.test function
kertosis skewness between minus one and one means good data
two samp test for expected dif
xbar dif minus mu dif then divide by denominator their var sq divide by samp size added to each other. pooled se denom
when equal var dof is sum sampsizr minus 2
same sampsize use two samp ztest
ftest test var equal
ttest small normal pop any var
normal means skew between 1 and plus one
kurt close 0
ttest check mean sig dif
pvalue two tail double one tail
pvalue checks chance if teo means same you see discrepency same or larger
alpha level percent is big
matched pairs before after
or placebo med match subjects same age gender from each group then flip coin determine who gets placebo
this negates blocking variables like ability age weight
And we would divide by total P7.
But now when we copy that down to get it for males,
we want the 7 to change to an 8.
When we copy this across, we don't want the P to change.
So I'll dollar sign that, okay.
same colimn dif row
chi square between sub categories associsted or dependent or dif variance affect categories compared
expected val for see what not indep will looks like
Expected values are calculated by multiplying the marginal row and
column totals and dividing by the overall total.
Chi square is then the sum of the expected values subtracted from
the observed value squared,
divided by the expected value with the degrees of freedom,
that is the product of the number of rows minus 1.
And the number of columns minus 1.
_____________ basically we
square the difference between the observed and
expected value and divide by the expected value like this.
Finally, we sum these values, obtain our chi square value
if less than crit value lookup dpf table no difference
eij means expected under independent
female prob times blue eyes prob times total
observe minus exp then sq then div by exp
chisq.dist.rt is pval
chisq.test need observe and expect value only dont need dof or chi sq total
_______________
multiple match
multiple match
aggregate ignore errors
divide logic tedt by itself since false is zerogive error
multiply row function so true can be ranked
https://youtu.be/fDB1Ktyhp3Y
delimiter split answer with symbol
textjoin need cse remember to keep in memory so much to search
filter isnumber search
hides missing boxes
click first result to reference
to get entire spill arrays range need hashtag in data analysis box
rrmovr error alert to allow incomplete searches not exact when you click dropdown
to incl corresponding company filter select company column as array and include customer column then type = and click search box
turn data in table to automatically update
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