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## Science & Study Basics- Overview

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**Ecological Methodology**LEC-01aAlthoff Science & Study Basics- Overview Scientific Method: HO vs. HATypes of Studies: Experimental vs. Observational**EXPERIMENTAL**INTERPRETATION ANALYSIS: Trends/Baseline EVALUATION OF METHODS INVENTORY & MONITORING**Scientific Method**Observation(s) Question Hypothesis Test does _______ hypothesis: make additional predictions and test them Test does _______ support hypothesis: revise hypothesis or pose new one Prediction Test: Experimental or Additional observation**Activity: Put these in proper order**• Conclusion • Experiment • Hypothesis • Observation(question) • Theory**Some important terms**• _______ = sample unit left as “normal” or untreated • _______ = sample unit that something “different” is done to it • _______ = assumes no bias due to human subjectivity • __________________ = independent variable • __________________ = dependent variable**Observational vs. Experimental Studies**• Observational: no controls (usually), trying to determine basics, learn patterns, trends, characteristics • Experimental: control (usually), have basic knowledge of subject that enables one to “separate” into treatment groups**Hypothesis**• = null hypothesis….essentially says “no differences” • = alternative hypothesis….essentially says “found differences”…with statistical evidence to support that**Observational vs. Experimental Studies**• Observational: generally summarize data using _____________ statistics • Experimental: determine if differences between treatments are “real” using _______________ statistics**Statistics**• Descriptive statistics: central tendency: mean, median, mode spread: range, variance, standard deviation, standard error relationship: correlation (Pearson, Spearman) • Inferential statistics: parametric: t-test, F-test, Analysis of Variance (ANOVA), chi-squared non-parametric: sign test, Kruskal-Wallis test, Friedman test • Models: Akaikae Information Criterion (AIC), Structural Equation Modeling (SEM)**Quail Eggs: Does Size Matter?**• Not all eggs laid are the same….can vary by: 1) weight/mass 2) yolk composition (protein & lipid %) 3) albumen composition (protein & water %) 4) shell thickness**Quail Eggs: Key components**3 2 Pre-incubation Mid-incubation**Quail Eggs: Does Size Matter?**• Normally take 23-24 days to hatch from start of incubation • Young born are __________…meaning they are “ready” to go (aka leave nest) within 6-24 hours after hatching • Eggs must be kept at 99-100 oF (99.5 oFbest) for the duration of the incubation period • 3 ways for us to “check” on development: 1) _______ eggs (expect weight will decrease) 2) _______ eggs (expect air space to increase) 3) _______ eggs (expect “light”/”dark” areas)**Quail Eggs: Checking Egg Status**• Weigh – using digital platform scale**Quail Eggs: Checking Egg Status**• Float – in beaker of water Sink Semi-float Float**Quail Eggs: Checking Egg Status**• Candling**The “Study” Design**Starting with 100+ eggs Placing in incubator with egg turner**Basics….**• Overall, eggs pre-incubation weighed from ________________ grams • To have “clear separation” of small vs. large eggs, will consider only eggs weight 11.3 g or less as _________12.4 g or greater as ___________ • Response variable: hatch within 24 hours of first hatch (= H24) _______ or less ____ or greater **Hypothesis & Statistical Test**• H0 - No difference in H24 between small and large eggs • HA - Difference in H24 between small and large eggs • Evaluate using Chi-Squared (X2) Hatch in H24 Small eggs (<11.3) (N = 28) Large eggs (<12.4) (N = 31)