Select Page

Lab Report I – Practice Section III – Weber’s Law

Round final answers to two decimal places. During the steps of any calculations, round to three decimal places.

Fill in the table below, and then answer the questions. Refer back to the Data Sheet when appropriate.

For the purposes of these questions, assume that:

1.  Any two PSEs that differ by 1.00 units or more are meaningfully different. Any two PSEs that differ by less than 1.00 units are not meaningfully different.
2.  Any two JNDs that differ by 1.00 units or more are meaningfully different. Any two JNDs that differ by less than 1.00 units are not meaningfully different.

Question 1: What is the slope of the best fitting line drawn through your data? (Just write the slope. Don’t explain what a slope is.)

Question 2: What is the Weber fraction for your data? (Just write the Weber fraction. Don’t explain what a Weber fraction is.)

Question 3: Is your variable error larger for larger stimuli (refer to your data)?

Question 4: Are you more precise when judging larger stimuli (refer to your data)?

Question 5: In general, does your accuracy increase when judging smaller stimuli (refer to your data)?

Question 6: According to Weber’s Law, for which weight would you be most likely to notice the addition of ten grams? (Weber fraction for weight is 0.07).

A. 1 Kilogram.

B. 2 Kilogram.

C. 3 Kilogram.

Question 7: Assume that a weight discrimination experiment produced the following results:

According to Weber’s Law, how large should the JND be for the standard stimulus of 400 g?

A. 10g.

B. 12g.

C. 16g.