Graphing and Data Collection Flashcards
Graph:
recorded data can be plotted on a graph
A graph is a:
pictorial representation of information recorded in a data table.
Why are graphs used:
to show a relationship between two or more different factors
When to use a line graph:
ued to show data that IS continuous and shows relationship between the independent and dependent variable
Points are connected
When to use a bar graph:
used to compare descriptive data like finite amounts, specific percentages or categories. Data is NOT continuous and the bars DON’T touch.
When to use a histogram:
used for intervals or ranges of data rather than one singal value. Data IS continuous and the bars DO touch
Independent Variable:
the variable that’s changed/manipulated by the scientist
Dependent Variable:
the variable that might change because of what the scientist changes: what’s being measured.
Controlled Experiment:
In a controlled experiment, all other aspects of the experiment must stay the same. These are known as constants.
DRY MIX:
D - dependent variable
R - responds to the change
Y - plotted on y-axis
M - manipulated to cause change
I - independent variable
X - plotted on the x-axis
Designing Controlled Experiments:
A hypothesis should be tested by an experiment in which only one variable is changed. All other variables should be kept unchanged, or controlled.
Controlling Variables:
If several variables are changed in the experiment, researchers can’t easily tell which variable is responsible for any results they observe.
Control and Experiment Groups:
Control groups are exposed to teh same conditions as the experimental group except for on independent variable.
Why would a scientist use a bar graph over a histogram?
A bar graph is used ti compare data that is NOT CONTINUOUS, while a histogram is used to show the RANGE of CONTINUOUS data.
Bar graph is categorical, not continuous, not discreet.
Histogram is continuous and expects data to be in the same range.
