Hector Plotquin
Prof. Hector Plotquin, LACC Mathematics Department
Office Hours / Class Schedule Spring 2019
Time 
Day 
Course 
Room 
9:35  10:45 am 
MTWTh 
Math 167: PreStatistics Class section 22113 
FH 121 
11:10 am  12:20 pm 
MTWTh 
Math 261: Calculus 1 Class section 20434 
FH 121


Online Course 
Math 167: PreStatistics Class section 24780 

12:30  1:30 pm 
MTW 
Office Hours 
FH 101F 
12:00  1:30 pm 
2nd Tuesday 
Aademic Rank Committee Meeting 
FH 100 
12:45  1:45 pm 
2nd Thursday
 Feb. 14
 Mar. 14
 Apr. 11
 May. 9
 Jun. 13
 Aug 8
 Sep 12
 Oct 10

Mathematics Department Meeting 
FH 100 
In this video, you will learn the basics of StatCrunch
including calculating basic summary statistics,
constructing simple graphs, interacting with those graphs,
and copying StatCrunch results into other applications.
StatCrunch is a webbased statistical software package
for analyzing data that works on any desktop browser,
such as Chrome, Firefox, Internet Explorer, or Safari.
StatCrunch also works with web browsers on smartphones
or tablets running iOS, Android, and other mobile operating
For this video, the dataset I'll be using
is called Responses to Is college worth it?
This dataset contains information
collected from a survey conducted at StatCrunch.com.
Respondents to the survey were asked
if college was worth the cost.
With the possible answers being yes, no, or unsure.
Respondents also provided their gender, age,
and if they were a current college student.
All right, now let's perform some basic operations
The Stat menu contains a number of procedures
for Summary Statistics, Tabulation, Hypothesis Testing,
Confidence Intervals, Regression, and much more.
With this dataset, I'll consider the task of computing summary
statistics for the mean and median ages of the respondents.
To accomplish this task, under the Stats menu,
I'll choose Summary Stats.
And now I'll select the Age column.
And StatCrunch generates a table of summary statistics.
The mean age of respondents is shown to be roughly 29.31.
And the median age of respondents
is shown much lower, at a value of 23.
To compute separate summary statistics
for each value of gender, back under the Options menu,
This takes us back to the original window
where we set up our table.
Now under Group by, I'll choose Gender.
The mean age of female respondents
and the mean age of male respondents
are both very close to 29.3.
The median age of both genders are exactly 23.
The Graph menu contains a number of options for displaying data
To summarize how respondents felt about college being
worth the cost, under the Graph menu,
I'm going to choose Bar Plot with Data.
I'm going to select the Good column, which
represents Is college worth it?
In this case, the plot indicates the overwhelming majority
of respondents said that college was worth the cost.
To break out these responses by gender,
I'll go back under the Options menu for the graph.
And in the Group by box, choose Gender.
Now the split bar plot, shown, splits the original responses
Note the majority of those who answered yes were female.
Most graphics in StatCrunch are interactive.
This can be a very powerful feature.
So for example, to identify the females who
said college was worth it, click and drag the mouse
to form a rectangle which overlaps that bar.
The selected data values are now highlighted in the graph,
and also highlighted in any other graphs produced.
The corresponding rows are also highlighted in the data table.
Clicking the Down or Up buttons in the lower left hand corner
will scroll the data table to show the next
or previous selected rows.
This is especially useful when there
is a small number of rows that have been
selected in a large data table.
Adjacent to these two Arrow buttons, the value of 582 rows
indicates how many rows have been selected.
To turn off highlighting, I'll click the Clear button
in the lower left hand corner of the screen.
Both tabular and graphical results
can be saved to your My Results listing at StatCrunch.com,
or they can be copied, printed, or downloaded.
To copy this bar plot, under the Options menu,
To finish copying the image, follow
the tip provided for your platform as shown.
After the image is copied, it can
be pasted into any other application such as Microsoft
Saving, printing, and downloading
are also available under the Options menu of the bar plot
Copying tabular results is even simpler.
Go ahead and click in the window of the table,
and just use standard keys on that platform
Such as ControlC or CommandC. Then use standard paste keys
and paste the results into an application