Casio fx-7400G User manual

Statistical Graphs and
Calculations
This chapter describes how to input statistical data into lists, and
how to calculate the mean, maximum and other statistical values. It
also tells you how to perform regression calculations.
1. Before Performing Statistical Calculations
2. Statistical Calculation Examples
3. Calculating and Graphing Single-Variable Statistical Data
4. Calculating and Graphing Paired-Variable Statistical Data
5. Manual Graphing
6. Performing Statistical Calculations
Chapter
7
Important!
• This chapter contains a number of graph screen shots. In each case, new data
values were input in order to highlight the particular characteristics of the graph
being drawn. Note that when you try to draw a similar graph, the unit uses data
values that you have input using the List function. Because of this, the graphs
that appears on the screen when you perform a graphing operation will prob-
ably differ somewhat from those shown in this manual.

94
Statistical Graphs and Calculations Chapter 7
1. Before Performing Statistical
Calculations
In the Main Menu, select the STAT icon to enter the STAT Mode and display the
statistical data lists.
Use the statistical data lists to input data and to perform statistical calculations.
1(GRPH) .... Graph menu
2(CALC)..... Statistical calculation menu
3(SRT•A).... Ascending sort
4(SRT•D) ... Descending sort
[
1(DEL) ....... Single data item delete
2(DEL•A).... Delete all data
3(INS) ........ Insert data item
Press [to return to the previous menu.
• The procedures you should use for data editing are identical to those you use
with the list function. For details, see “Chapter 6 List Function”.
2. Statistical Calculation Examples
Once you input data, you can use it to produce a graph and check for tendencies.
You can also use a variety of different regression calculations to analyze the data.
Example To input the following two data groups and perform statistical
calculations
0.5, 1.2, 2.4, 4.0, 5.2
–2.1, 0.3, 1.5, 2.0, 2.4
1234[
1234[
P.81
P.82
P.82
P.78
Use f , c , d and e to move
the highlighting around the lists.
P.95
P.113
P.83
P.84

95
Statistical Graphs and Calculations Chapter 7
kk
kk
kInputting Data into Lists
Input the two groups of data into List 1 and List 2.
a.fwb.cw
c.ewewf.cw
e
-c.bwa.dw
b.fwcwc.ew
Once data is input, you can use it for graphing and statistical calculations.
• Input values can be up to 10 digits long (9-digit mantissa and 2-digit exponent
when using exponential format). Values in statistical data table cells are shown
only up to six digits.
• You can use the f, c, dand ekeys to move the highlighting to any cell in
the lists for data input.
kk
kk
kPlotting Data
Example To specify Graph 1 as non-draw (OFF) and Graph 3 as draw (ON)
and use Graph 3 to plot the data you input into statistical data
List 1 and List 2 above
While the statistical data list is on the display, press 1(GRPH) to display the graph
menu.
1(GRPH)
1(GPH1)..... Graph 1 draw
2(GPH2)..... Graph 2 draw
3(GPH3)..... Graph 3 draw
[
1(SEL)......... Graph (GPH1, GPH2, GPH3) selection
4(SET) ........ Graph settings (graph type, list assignments)
Press [to return to the previous menu.
• You can specify the graph draw/non-draw status, the graph type, and other gen-
eral settings for each of the graphs in the graph menu (GPH1, GPH2, GPH3).
• You can press any function key (1,2,3) to draw a graph regardless of the
current location of the highlighting in the statistical data list.
• The initial default graph type setting for all the graphs (Graph 1 through Graph 3)
is scatter diagram, but you can change to one of a number of other graph types.
P.97
1234[
1234[

96
Statistical Graphs and Calculations Chapter 7
kk
kk
kPlotting a Scatter Diagram
It is often difficult to spot the relationship between two sets of data (such as height
and shoe size) by simply looking at the numbers. Such relationships often become
clear however, when we plot the data on a graph, using one set as x-values and the
other set as y-values.
uu
uu
uTo plot a scatter diagram
Example To plot the data we input in statistical data List 1 and List 2
1(GPH1)
• The default setting automatically uses List 1 data asx-axis values and List 2 data
as y-axis values. Each set of x/ydata is a point on the scatter diagram.
• To return to the statistical data list, press Q.
kk
kk
kChanging Graph Parameters
Use the following procedures to specify the graph draw/non-draw status, the graph
type, and other general settings for each of the graphs in the graph menu (GPH1,
GPH2, GPH3).
1. Graph draw/non-draw status (SELECT)
The following procedure can be used to specify the draw (On)/non-draw (Off) status
of each of the graphs in the graph menu.
uu
uu
uTo specify the draw/non-draw status of a graph
1. While the graph menu is on the display, press [1(SEL) to display the graph
On/Off screen.
1(GRPH)
[1(SEL)
1(On).......... Graph On (graph draw)
2(Off).......... Graph Off (graph non-draw)
4(DRAW).... Draw all On graphs
• Note that the S-Grph1 setting is for Graph 1 (GPH1 of the graph menu), S-Grph2
is for Graph 2, and S-Grph3 is for Graph 3.
1234

97
Statistical Graphs and Calculations Chapter 7
2. Usefand cto move the highlighting to the graph whose draw (On)/non-draw
(Off) status you want to change and press 1(On) or 2(Off).
3. To return to the graph menu, press Q.
uu
uu
uTo draw a graph
Example To draw a scatter diagram of Graph 3 only
1(GRPH)[1(SEL)
2(Off)
cc1(On)
4(DRAW)
2. General graph settings (SET)
This section describes how to use the general graph settings screen to make the
following settings for each graph (GPH1, GPH2, GPH3).
• Graph Type
The initial default graph type setting for all the graphs is scatter graph. You can select
one of a variety of other statistical graph types for each graph.
• List
The initial default statistical data is List 1 for single-variable data, and List 1 and List
2 for paired-variable data. You can specify which statistical data list you want to use
for x-data and y-data.
• Frequency
Normally, each data item or data pair in the statistical data list is represented on a
graph as a point. When you are working with a large number of data items however,
this can cause problems because of the number of plot points on the graph. When
this happens, you can specify a frequency list that contains values indicating the
number of instances (the frequency) of the data items in the corresponding cells of
the lists you are using for x-data and y-data. Once you do this, only one point is
plotted for the multiple data items, which makes the graph easier to read.
• Mark Type
This setting lets you specify the shape of the plot points on the graph.
1234

98
Statistical Graphs and Calculations Chapter 7
uu
uu
uTo display the general graph settings (SET) screen
While the graph menu is on the display, press [4(SET) to display the general
graph settings screen.
1(GRPH)
[4(SET)
• The settings shown here are examples only. The settings on your general graph
settings screen may differ.
uu
uu
uTo select the StatGraph area
1. While the general graph settings screen is on the display, use fand cto
move the highlighting to the StatGraph item.
2. Use the function key menu to select the StatGraph area you want to select.
1(GPH1)..... Graph 1
2(GPH2)..... Graph 2
3(GPH3)..... Graph 3
uu
uu
uTo select the graph type (G-Type)
1. While the general graph settings screen is on the display, use fand cto
move the highlighting to the G-Type item.
2. Use the function key menu to select the graph type you want to select.
1(Scat) ....... Scatter diagram
2(xy)........... xy line graph
[
1234
1234[
1234[

99
Statistical Graphs and Calculations Chapter 7
1(Hist) ........ Histogram (bar graph)
2(Box) ........ Med-box graph
3(N•Dis) ..... Normal distribution curve
[
1(X) ............ Linear regression graph
2(Med) ....... Med-Med graph
3(X^2) ........ Quadratic regression graph
[
1(Log) ........ Logarithmic regression graph
2(Exp) ........ Exponential regression graph
3(Pwr) ........ Power regression graph
Press [to return to the previous menu.
uu
uu
uTo select the x-axis data list (XList)
1. While the graph settings screen is on the display, use fand cto move the
highlighting to the XList item.
2. Use the function key menu to select the name of the statistical data list whose
values you want on the x-axis of the graph.
1(List1)....... List 1
2(List2)....... List 2
3(List3)....... List 3
4(List4)....... List 4
[
1(List5)....... List 5
2(List6)....... List 6
Press [to return to the previous menu.
1234[
1234[
1234[
1234[

100
Statistical Graphs and Calculations Chapter 7
uu
uu
uTo select the y-axis data list (YList)
1. While the graph settings screen is on the display, use fand cto move the
highlighting to theYList item.
2. Use the function key menu to select the name of the statistical data list whose
values you want on the y-axis of the graph.
1(List1)....... List 1
2(List2)....... List 2
3(List3)....... List 3
4(List4)....... List 4
[
1(List5)....... List 5
2(List6)....... List 6
Press [to return to the previous menu.
uu
uu
uTo select the frequency data list (Frequency)
1. While the general graph settings screen is on the display, use fand cto
move the highlighting to the Frequency item.
2. Use the function key menu to select the frequency setting you want.
1(1) ............ Plot all data (1-to-1)
2(List1)....... List 1 data is frequency data.
3(List2)....... List 2 data is frequency data.
4(List3)....... List 3 data is frequency data.
[
1234[
1234[
1234[
1234[

101
Statistical Graphs and Calculations Chapter 7
1(List4)....... List 4 data is frequency data.
2(List5)....... List 5 data is frequency data.
3(List6)....... List 6 data is frequency data.
Press [to return to the previous menu.
uu
uu
uTo select the plot mark type (M-Type)
1. While the general graph settings screen is on the display, use fand cto
move the highlighting to the M-Type item.
2. Use the function key menu to select the plot mark you want to select.
1( ) ........... Plot using
2(X) ............ Plot using X
3(•) ............. Plot using •
kk
kk
kDrawing an xy Line Graph
Paired data items can be used to plot a scatter diagram.A scatter diagram where the
points are linked is an xy line graph.
Press Qto return to the statistical data list.
kk
kk
kSelecting the Regression Type
After you graph statistical data, you can use the function menu at the bottom of the
display to select from a variety of different types of regression.
1(X) ............ Linear regression graph
2(Med) ....... Med-Med graph
3(X^2) ........ Quadratic regression graph
1234
1234[
P.98
(G-Type)
(xy)

102
Statistical Graphs and Calculations Chapter 7
[
1(Log) ........ Logarithmic regression graph
2(Exp) ........ Exponential regression graph
3(Pwr) ........ Power regression graph
4(2VAR) ..... Paired-variable statistical results
Press [to return to the previous menu.
kk
kk
kDisplaying Statistical Calculation Results
Whenever you perform a regression calculation, the regression formula parameter
(such as aand bin the linear regression y= ax + b) calculation results appear on the
display. You can use these to obtain statistical calculation results.
Regression parameters are calculated as soon as you press a function key to select
a regression type while a graph is on the display.
Example To display logarithmic regression parameter calculation results
while a scatter diagram is on the display
[1(Log)
kk
kk
kGraphing statistical calculation results
You can use the parameter calculation result menu to graph the displayed regres-
sion formula.
3(COPY) .... Stores the displayed regression formula as a graph function
4(DRAW).... Graphs the displayed regression formula
1234[
1234
P.110