WEEK 7

Question 1

Confidence Intervals

Answer 1

-We can use the sample mean as an estimate of the population mean

-Sample Mean: Mean of your sample (a subset of the population)
-Population Mean: Mean in the population

Question 2

Point and Interval Estimates

Answer 2

• We can calculate boundaries within which we think the population will fall (confidence intervals)
• A sample mean is known as the point estimate

Question 3

e.g. confidence intervals

Answer 3

• 1.96 standard deviations above and below the mean includes 95% of the standard normal distribution
  95% confidence that our sample mean will be within 1.96 standard deviations of the population mean

Question 4

Limitations of standard error

Answer 4

• Small Samples have larger confidence intervals
  -Larger samples have narrower confidence intervals

Question 5

What is a hypothesis?

Answer 5

• A precise statement of an assumed relationship between variables, a prediction about how something will behave
  -must be testable

Question 6

Types of Research:

Answer 6

• Causal: suggests a particular causal influence
  non-causal: suggests a particular characteristic without reference to causation

Question 7

Types of Hypothesis:

Answer 7

-Directional; suggests a direction of the effect
-non-directional: does not specify the direction of the difference/ effect

Question 8

One tailed vs two tailed hypothesis

Answer 8

• One tailed: where you HAVE specified the direction of the relationship between variables or the difference between conditions

Two-tailed: you have NOT specified the direction of the relationship, bit you have stated there will be/ wont be one

Question 9

Null VS Alternative hypothesis

Answer 9

Null: No effect
Alternative: Is an effect

Question 10

What is a sampling error?

Answer 10

• The patterns in our scores do not accurately reflect the underlying population

Question 11

P Value+ Hypothesis testing

Answer 11

-how likely we are to get the pattern of data we have found if the null hypothesis were true
- known as the P VALUE
p: 0.05 or 1/20

if p>0.05 we do not have sufficient evidence to reject the null hypothesis
if p<0.05 we have sufficient evidence to reject the null hypothesis

Question 12

Null Hypothesis and Significance Testing

Answer 12

1. Formulate a hypothesis and collect data to measure this
2. Run statistical analyses on the data using SPSS to produce a test statistic
3. Test statistic is compared in SPSS to work out how likely it is to obtain the statistic if the null hypothesis was true
4. if p is small enough, it suggests that the pattern of findings is unlikely to have arisen by chance, meaning the data is statistically significant