Investigating Science - Module 7
What is a placebo
A substance or effect with no real therapeutic value. (no effect) Example - Sugar pill in contraception.
Sample size in soap compared to hand-sanitiser
Large sample size - 3-5 repeats of each Opportunity sampling - hand-sanitiser and soap were readily available
Evidence that refutes Coca-Cola's claims
Sugar and calorie content not for fitness. Unhealthy, and doesn't display values on the ad.
What is observer bias?
Tendency to see what we expect to see, or what we want to see.
What are examples of emotive advertising in Coca-Cola advertisements?
"Open a coke, open happiness" Related to emotions - "Taste the feeling" 'Hot, fit' people always used in advertisements
What are examples of pseudoscience?
Astrology - Starsigns Numerology - Numbers predict life Iridology - Alternative medicine based on the iris of the eye.
Social influence on the suggestion of remedies for health conditions
Celebrities use their influence to convince people to purchase alternative remedies.
What is the halo effect?
Cognitive bias in which our overall judgment of how a person influences how we think and feel. Celebrity ads instead of homeless people advertising.
Validity in Soap compared to hand-sanitiser
Controlling variables, placement and volume of hand sanitiser
What are the ethics of placebo use?
Ensure patients are not missing out on life saving treatment by receiving placebo and not knowing.
What are double-blind trials?
Experimenter and participants do not know who is receiving a particular treatment. Useful to reduce observer bias and stop a placebo effect from occurring because no one knows who has what.
Economic influence on the prediction of climate change
Fossil fuel companies spent a lot of money sponsoring scientists to say it is not warming, so they can continue to use fossil fuels.
How do scientists determine sample size?
Looking at the confidence level and interval to determine how accurate a sample represents a population.
Economic influence on the suggestion of remedies for health conditions
May be based on sponsorship from other countries.
Social influence on the manipulation of data
Media reports on things to get a reaction from the public. For example, studies could have a small sample size or focus on mode/mean rather than median.
Societal influence on the prediction of climate change
People are concerned about the Earth falling into another ice age. Now temperature is found to be rising.
What are examples of correlation without causation?
People modify their behaviour in response to their awareness of being observed. A study that linked hormone replacement therapy to coronary heart disease -of women developing heart disease was related to women taking estrogen. Mozart effect - Listening to classical music improves the brain.
What is the placebo effect
Produced by a placebo drug or treatment. Example - taking an exercise placebo drug and still gaining muscle due to working out.
What are the different methods of sample selection?
Random - Every subject has an equal chance of being selected. Stratified - Divide population into subcategories and ensure this is a representation of the population. Volunteer-sampling - 'self-selected' subjects volunteer to be in the study Opportunity - Selecting people available at the time
Reliability in soap compared to hand-sanitiser
Repeats and closeness of the range. High number of agar plates.
Accuracy in soap compared to hand-sanitiser
Ruler used to find surface area of bacteria
What is the concept of publish or perish?
Scientists need to publish work to be paid as they aren't self funded. As such, some scientists attempt to publish intentionally fraudulent papers for an income. The peer review process is meant to have 3 different widely cited and respected scientists review it, but many papers get to publishing without being reviewed at all.
Economic influence on the manipulation of data
Scientists under pressure to public - a lack of or poor research to convince statistical evidence.
What is sample selection?
Selecting a representative group from the population under study
What is a sample size?
The number of observations or replications in an experiment.
What are control groups?
The standard to which comparisons are made in an experiment. Example - An agar plate with no treatment.
Does the data collected in soap compared to hand-sanitiser support or refute the claim that hand-cleaners have anti-bacterial properties?
Yes, it supports it. Less bacterial growth than control plate.
What is an example of the falsification of results?
Yoshihiro Sato. Bone researcher His randomised groups were too similar to each other, and there were low rates of drop outs in large cohorts. He was able to have a 70-80% reduction in hip fractures, far too high a value.