Download Laboratory 1

Lab 1. Overview
 Instructor Introduction & Syllabus Distribution
Attendance – Don’t miss labs.
Assignments – Things are due EVERY week.
See calendar/table in syllabus.
 Lab Safety (Students sign contracts).
 Science, Hypothesis Testing, and Syllabus
 Complete and turn in in-class exercise.
 Termite Study Introduction.
 Design and conduct your termite study.
 Exercise due in Lab 2 discussion & questions
Science
 Science = Knowing the world based on the
belief that phenomena have natural,
predictable causes that can be revealed by
sensory (empirical) evidence.
 Assertions must be testable (able to be rejected).
 Scientific doubt - Can only say
PROBABLY or NO ≈ SUPPORT or REJECT
 Replication = repeating observations.
More replication = More likely = better study
 Quantification = making data numerical;
increases precision and ability to repeat.
Scientific Studies
 Comparative Studies = hypotheses
predict patterns in nature
 Experimental Studies = hypotheses
predict patterns based on manipulation
Experimental Group = given treatment
Negative Control (Group) = treated like the exper.
group, BUT does no treatment –The basis for
comparison.
Positive Control (Group) = treatment is applied to
a situation with a known outcome – Identifies
errors in the procedure.
Variables
 Independent variable = manipulated or
varying condition – On x-axis if graphed.
 Dependent variable = measured response
(usually quantitative; often called “the” data) – The yaxis if results are graphed.
Descriptive Statistics = Summarize a set of
data.
Mean = Average
 Probabilistic Statistics = Determine if groups
of data show “chance” similarity.
e.g., Can answer, “Is the difference between the means of
my data taken for the experimental group and the
negative control group significant?”
Using Data and P-Values
P-value = “probability of error;” (0.05 =5%).
P-value  0.05 = significantly different.
Unpaired t-test = compares means; gives a P-value.
Testing a Hypothesis of Difference Between Means
1. Compare Means to Hypothesis ↓
* If inconsistent with hypoth., reject the hypoth.
* If consistent with hypoth., then do 2 ↓.
2. Use a t-test to Calculate a p-value
* If p > 0.05, then reject the hypothesis (= not
significantly different). (Treat means as “same.”)
* If p ≤ 0.05, then the hypothesis is supported,
the consistent means = significantly different.
Scientific Investigations
 Termites follow blue Papermate® pen.
Develop a hypothesis as to what they are
following (sight, scent, touch, etc.)
Develop and conduct a REPLICATED
experiment involving QUANTITATIVE data to
test your hypothesis.
KEEP IT SIMPLE (2-3 conditions)
MAKE PATH CIRCULAR
WRITE DOWN YOUR QUANT. DATA
• READ the instructions () in the manual
Termite