Bio 1406 Lab 1 Collecting and Analyzing Data
Discrete Random Variable
an integer of something counted ie. # of times a coin is tossed, number of students enrolled in class . - A quantitative value
Statistical Analysis
analyze how precise and accurate our data is.
Observations variance from one experiment to the next
known as experimental or random variables
Qualitative Value
description that is not reported in numbers ie. buffering capacity (small or large), the dog looked happy, 46% of class is female.
Standard Deviation
shows how far the measured (experiment) values deviated from each other and the mean. It measures how precise the value are. Less variation= smaller deviation.
System of Units (SI units) aka the metric system
1. used by scientist around the world 2. easy to convert from one unit to another since they are related by units of 10 nano 10^-9 micro 10^-6 milli 10^-3 centi 10^-2 deci 10^-1 Base Unit 1x 10^0 deca 10^1 kilo 10^3
Micropipetters measure volumes of 1mL or less
3 size of Micropipettes: 2-20 uL 20-200 uL 100-1000 uL (1mL = 1000 uL) to use: adjust knob to correct uL needed, attach a tip, press down plunger to first stop then place tip in liquid and slowly release to draw up the liquid. to release- push down plunger to second stop, a little air will completely empty the tip to deliver correct volume.
Pipettes measure volumes 1mL or greater
4 sizes of Pipettes: 10mL (green) 5mL (green) 2mL (blue) 1mL (blue) to use: place tip into the liquid and draw it up into pipette using thumb screw. To measure 4ml, bring liquid to 5ml, then release it to the 1ml mark.
Scientific Investigation
based on observations or information we collect using sense of sight, sound,smell, taste, and touch.
Accuracy
measure how close measured value come to true value. *measurement of the correctness of the result
Percent Error
measure of accuracy by determining how far the measured values deviate from the true value. mean= experiment measured value true (accepted ) value= desired value Percent error: absolute value of (mean-true value)/true value, then multiply by 100.
Precision
measure of consistency and is sometime referred to as reproducibility. *precise measure does not vary over several trials.
Mean
measure of precision by taking average of group of numbers. Mean= (sum of measured values)/ (# of trials)
Continuous Random Variable
positive whole number of something measured. a Quantitative Value. ie. length of hair strand
Quantitative Value
specific number ie. this soup has 185 mg sodium per serving
