Why can we not add and subtract fractions with different denominators?
We cannot add and subtract fractions with different denominators since the units, or size of the parts are different. The denominator represents how many parts the whole was split into. For example we can split a dollar into tenths (10 dimes) or hundredths (100 pennies), the whole dollar has been split into different sized parts but the value has stayed the same. If I were to take one penny away from one dollar and one dime away from another dollar, the amount left over would be different. Why? Because the size of the parts were different. To subtract and add fractional parts they must have the same value, or represent the same part of the whole.
What is one counterargument to Searle's Chinese Room Argument?
One counterargument to the strong AI claims in Searle's Chinese Room thought experiment is that the program is not operating alone. There is a larger system at play that does understand Chinese. For example, for someone to have generate the cards and programmed the computer they must have had an understanding of the language, making it irrelevant that Searle does not understand Chinese, since the larger system at play does.
What are the possible solutions a researcher can employ to reduce the threats of internal validity of single subject designs?
One of the biggest threats to internal validity in single subject research is subject bias. A researcher can employ a ABCB design testing for a placebo effect or the researcher can conduct multiple baselines to mitigate the effects of subject bias.