StatCrunch: Hypothesis Tests and Confidence Intervals for Two Means with Raw Data Video Lecture | Statcrunch Tutorials for Beginners - Data & Analytics

in this video you will learn to compute
hypothesis tests and confidence
intervals for the difference between two
means with raw data using statcrunch the
data set i'll be using is called asking
prices for four-bedroom homes and Bryan
College Station Texas this data set
compares four bedroom homes listed for
sale in two adjoining cities Bryan Texas
and College Station Texas it consists of
a random sample of 15 homes listed for
sale in Bryan and 15 homes listed for
sale and College Station the square
footage column contains the square
footage of each home and the location
column lists the city where the home is
located this video will cover how to
compute a two sample T hypothesis test
and a two sample T confidence interval a
similar approach can be used for two
sample Z methods that are appropriate
for situations with larger sample sizes
and/or known standard deviations for
this video the statistical question I'm
going to test is is there a significant
difference in the average size of four
bedroom homes listed for sale in the two
cities to do this I'm going to go under
the stat menu choose T stats to sample
with data under sample one our values
are listed in the square footage column
for sample one I want to limit the homes
from the first sample to Bryan Texas so
to do that in the where box I'm going to
type location equals quotation Brian
Texas note that statcrunch is case
sensitive so you need to make sure that
it is exactly how it appears in the data
table with capital letters and with
spaces under sample two again we'll
choose the square footage column but
this time I want to limit the second
sample to
College Station so again I'll type
location equals and this time College
Station Texas by default statcrunch is
going to perform a hypothesis test for
this situation then we're going to leave
the null at zero to compare the
difference in the two means and for the
alternative there are different options
you can have not equal to less than or
greater than
for this example we'll leave it at not
equal to I'll click compute the output
table provides various statistics from
the test including the test statistic
and the p-value now instead of computing
a hypothesis test let's compute a
confidence interval between for the
difference between the two means under
options choose edit this takes us back
to the original window where we set up
our test and this window statcrunch has
other options for the user to choose
underperform instead of choosing
hypothesis test this time we'll choose
confidence interval by default
statcrunch has a value of zero point
nine five for the level which will
produce a 95% confidence interval for
the difference between the two means for
this example I'll enter 0.99 which will
produce a 99% confidence interval I'll
click compute the results now show a 99%
confidence interval for the difference
in the mean square footage of four
bedroom homes where L limit represents
the lower limit and you limit represents
the upper limit lastly statcrunch can
also add our results to the data table
for future calculations to do so go back
under options edit and under output
choose the option store and data table
I'll click compute and now you can see
our results are now stored in new data
columns