Intro to Stats and AP Stats
A commercial food lab compared recipes for chocolate chip cookies. They baked cookies with different kinds of chips (milk chocolate, dark chocolate, and semi-sweet). All other ingredients and amounts were the same. Ten trained tasters rated the cookies on a scale of 1 to 10. The cookies were presented to the tasters in random order.
How was control used?
A commercial food lab compared recipes for chocolate chip cookies. They baked cookies with different kinds of chips (milk chocolate, dark chocolate, and semi-sweet). All other ingredients and amounts were the same. Ten trained tasters rated the cookies on a scale of 1 to 10. The cookies were presented to the tasters in random order.
How was randomization used?
A commercial food lab compared recipes for chocolate chip cookies. They baked cookies with different kinds of chips (milk chocolate, dark chocolate, and semi-sweet). All other ingredients and amounts were the same. Ten trained tasters rated the cookies on a scale of 1 to 10. The cookies were presented to the tasters in random order.
How was replication used?
Having at least one 15-minute warm-up session per week resulted in a drastic reduction in tears in the ACL. In a study involving about 4500 teen girl soccer players in Sweden, one group was randomly assigned to warm up with a neuromuscular exercise session. This group had 64% fewer ACL tears than the control group.
How was control used?
Having at least one 15-minute warm-up session per week resulted in a drastic reduction in tears in the ACL. In a study involving about 4500 teen girl soccer players in Sweden, one group was randomly assigned to warm up with a neuromuscular exercise session. This group had 64% fewer ACL tears than the control group.
How was randomization used?
Having at least one 15-minute warm-up session per week resulted in a drastic reduction in tears in the ACL. In a study involving about 4500 teen girl soccer players in Sweden, one group was randomly assigned to warm up with a neuromuscular exercise session. This group had 64% fewer ACL tears than the control group.
How was replication used?
Scientists at a major pharmaceutical firm investigated the effectiveness of an herbal compound to treat the common cold. They exposed each of the 50 subjects to a cold virus, then randomly assigned him or her either the herbal compound or a sugar solution known to have no effect on colds. Several days later they assess the patient's condition using a cold severity scale ranging from 0 to 5. They found no evidence of benefits associated with the compound.
How was control used?
Scientists at a major pharmaceutical firm investigated the effectiveness of an herbal compound to treat the common cold. They exposed each of the 50 subjects to a cold virus, then randomly assigned him or her either the herbal compound or a sugar solution known to have no effect on colds. Several days later they assess the patient's condition using a cold severity scale ranging from 0 to 5. They found no evidence of benefits associated with the compound.
How was randomization used?
Scientists at a major pharmaceutical firm investigated the effectiveness of an herbal compound to treat the common cold. They exposed each of the 50 subjects to a cold virus, then randomly assigned him or her either the herbal compound or a sugar solution known to have no effect on colds. Several days later they assess the patient's condition using a cold severity scale ranging from 0 to 5. They found no evidence of benefits associated with the compound.
How was replication used?
A swimsuit manufacturer wants to test the speed of its newly designed suit. The company designed an experiment by having 6 randomly selected Olympic swimmers swim as fast as they can with their old swimsuit first and then swim the same event again with the new, expensive swimsuit.
What is the problem with the control?
A swimsuit manufacturer wants to test the speed of its newly designed suit. The company designed an experiment by having 6 randomly selected Olympic swimmers swim as fast as they can with their old swimsuit first and then swim the same event again with the new, expensive swimsuit.
What is the problem with the randomization?
A swimsuit manufacturer wants to test the speed of its newly designed suit. The company designed an experiment by having 6 randomly selected Olympic swimmers swim as fast as they can with their old swimsuit first and then swim the same event again with the new, expensive swimsuit.
What is the problem with the replication?