Capacity

Question 1

Capacity

Answer 1

the amount of information that can be held in a memory store

Question 2

Jacobs (1887) research

Answer 2

developed technique to investigate the capacity of STM. He gave 4 digits to pps to recall in order and if correct increase number of digits by one until correct. This determines individual’s digit span. mean digit was 9.3 items, letter was 7.3 items.

Question 3

Miller (1956) research

Answer 3

Noted things come in sevens e.g. days of week, deadly sins, so suggested capacity is 7 items (plus or minus 2).
Also noted recall 5 words as well as recall 5 letters so came up with chunking.

Question 4

Weakness of Jacob

Answer 4

Conducted a long time ago.
Earlier research lacked control e.g. distracted, lacks internal validity due to confounding variables.
Furthermore, done long time ago, so findings not generalisable to memory now,
Research lacks validity

Question 5

However of Jacob

Answer 5

Replicated research
Bopp and Verhaegen (2005) found similar results.
Results are reliable so has good internal validity.
Research reliable and valid so generalisable.

Question 6

Weakness of Miller

Answer 6

Overestimated capacity of STM.
Cowan (2001) reviewed other research found 4 chunks.
Real number lower end, not 7 items, decreases validity of findings.
Further research to confirm these ideas