Recap: How People learn

1
Recap How People learn

• Classical conditioning
• Natural responses
• Operant conditioning
• Reward based (non-natural)
• Cognitive Psychology
• Whats going on in the brain
• Eg. learning to read (observable, recognition,
  autonomous

2
How people learn cont.

• Constructivism
• How individuals develop new knowledge
• Previous exp.
• Explanations
• Expectations
• Experiment
• Conclusions

Observations Hypothesis Predictions
3
Scientific Method

• What is the scientific method
• Observation
• Compare to other experimental results
• If both do not agree?
• Consistent with predictions
• No reject hypothesis and formulate a new
  hypothesis
• Similarities with learning?
• New information
• Compare to previous knowledge
• Different from prior knowledge?
• Reject prior or current information seek out
  more information

4
Hypothesis
Hypothesis A potential explanation.
Prediction An expected outcome based on the
hypothesis.
5
Scientific Processfact or fiction?

• Idealized method
• Start anywhere
• Not all learning needs experiments, but
  experiments are a powerful way of supporting or
  refuting hypotheses.

6
Hypothesis

• a proposal intended to explain certain facts or
  observations.
• The hypothesis should describe the expected
  relationship between the observation and the
  independent variable but not the actual
  experiment (cause and effect approach).
• What is the independent variable?
• Some examples.

7
(No Transcript)
8
Do you prove hypotheses?

• An experiment NEVER proves a hypothesis
• - A hypothesis that successfully predicts
  something is a good hypothesis it is supported.
• Why is this? because you can never rule out that
  another hypothesis exists that makes the same
  predictions.
• If two hypothesis make the same predictions, but
  for different reasons, how can you tell which is
  right? More experimentation is the answer.
• Theory A hypothesis that has withstood many
  attempts to falsify it.
• Law A well established theory with broad
  explanatory power.

9
Shifts in What is Known to be scientifically
true

• Greek shepherd observing sun movement, moon and
  stars.
• The cosmos is moving around us and earth is the
  center of it all
• This hypothesis was undeniable based upon the
  evidence available at the time
• But, other stars moved rather strangely
• Claudius Ptolemy (greek philosopher) proposed
  another hypothesis (very similar to first) in
  which these objects could move in the patterns
  noted.this thinking lasted, unfalsefied, for
  1500 years.

10
Nicholas Copernicus

• The earth was not the center of everything!
• He hypothesized that the Earth was just a planet
  orbiting the sun and spinning on its own axis.
• Now we have two hypotheses! Which is correct?
• More refined observations, experiments, etc. were
  conducted and we now have been living with the
  Copernican model for the last 500 years.
• Lets see what the future brings.

11
Experiment Design (KISS Principle)

• Keep it simple
• Experimental terminology

12
Prediction

• The prediction is based upon the experiment
  designed to test the hypothesis
• If two almond groves are under different watering
  regimes (schedules) then I would predict that the
  greater watered grove has a higher almond yield
  than the less watered grove.
• The prediction includes the independent variable
  and the dependent variable of the experiment.

13

• Independent Variable The variable the
  experimenter manipulates. (eg. amount of water)
  (almond study)
• Dependent Variable The variable the
  experimenter measures to describe the response.
  (eg. weight of almonds harvested)
• Control Group A group in which the experimental
  treatment is not applied. Used as a standard for
  comparison.
• 2 main types
• No treatment
• Natural
• Factors to be held constant Any factors that
  might affect the results other than the
  independent variable

14

• Observation A cannon ball falls faster than a
  feather, and cannon balls are heavier than
  feathers.
• The question Does mass affect how fast an object
  falls?
• Hypothesis Heavier objects fall faster because
  the force of gravity acts more strongly on larger
  masses.
• Hypothesis-based Prediction If the above
  hypothesis is correct, then if we compare the
  rate of movement of two objects that differ only
  in mass and are accelerated solely by gravity,
  the heavier object should move faster.
• Now we can set up an experiment where only mass
  varies then if the different masses move at the
  same speed, the hypothesis is falsified, but if
  they move at a different speed, it is supported.

15

• Experiment
• Method Balls that weigh either 10 grams or 50
  grams, but with the same diameter, are rolled
  down the same ramp with a 1 meter distance marked
  on it. Each ball will be placed behind a wooden
  barrier at the top of the ramp. This barrier
  will be removed to allow the ball to roll down
  the ramp without being pushed. The time it takes
  each ball to travel the 1 meter will be measured
  in seconds.
• Sample size 20 balls of each mass will be used.
  The experiment is relatively easy to conduct, and
  the only limitation is availability of balls, so
  there is no good reason to do less. 20 samples
  per group is generally considered an adequate
  sample size for a comparison of means.
• Independent variable The independent variable
  is the mass, in grams, of each ball.
• Dependent variable The dependent variable is
  the time, in seconds, each ball takes to travel
  1m.
• Factors to be held constant The following
  variables will be held constant across
  treatments the diameter of all balls the slope
  of the ramp the distance each ball travels
  during measurement (1 m) the way the balls are
  released.
• Control group There is no control group in this
  experiment. A control group would consist of
  balls with no mass a physical impossibility.

16
Data representation Comparison of means
Time for ball to travel 1 m (seconds)
Time for ball to travel 1 m (seconds)
Heavy Light
Heavy Light
A. Supports hypothesis
B. Falsifies hypothesis
Figure 1. Potential relationships between the
mass of the ball and the time for it to roll 1 m.
A If hypothesis is correct and B if
hypothesis is incorrect.
17
Science Process Skills

• Observing
• Classifying
• Communicating
• Measuring
• Formulating Hypothesis
• Predicting
• Identifying and controlling variables
• Testing hypothesis (a.k.a. experimenting)
• Interpreting data