Question

For the first correlation reported in the results section 3.3:

1. What are the variables used in the correlation?
2. For each variable, is it nominal, ordinal, interval, or ratio?
3. Is it a strong correlation? Why?
4. Is it positive or negative? How do you know?
5. Is the correlation statistically significant?

Please help! Thanks!

3.3. Sleep Two participants, whose sleep could not be recorded completely due to technical problems, were excluded from Table 2 Reaction times (ms) Wake Sleep Mean SEM Mean SEM Old 848 949 40 Angry faces 31 .113 846 899 898 38 Neutral faces 876 31 .577 Happy faces All faces 905 31 24 878 .709 876 25 25 New -314 .112 Angry faces 851 27 883 35 884 899 Neutral faces 822 36 36 853 842 Happy faces All faces .365 29 889 36 .174 Difference old-new Angry fac 34 .225 es 47 ー38 Neutral faces 53 .174 48 48 Happy faces All faces 494 584 52 29 34 sleep analysis. Polysomnographic recordings from the -0.54, p=.108. neutral:-0.59. p=.071). Neither NonREM remaining subjects confirmed a normal distribution of sleep sleep overall nor any sub-stage of NonREM sleep correlated stages during consolidation sleep in the night after learning (stage 1 sleep, 3.2 10%, stage 2 sleep, 59.3 2.6%, SWS 18.7 2.5%, REM sleep 17.4 1.17%, wake time 0.3 0.1 total sleep time 441.814.8 min, sleep onset 11.5 t 2.4 min) Correlations between recognition performance and sleep parameters showed that in the sleep condition overall mem- boredom, concentration, and tension obtained at learning ory accuracy was strongly correlated with the amount ofand recognition testing did not differ between sleep and NonREM sleep during consolidation sleep (r=.79, wake conditions (sleep vs. wake means± SEM at learning p .007; Fig. 2a). Hit rate or false alarm rate alone were no significantly associated with NonREM sleep (r=.36, vs. 3.25士0.31, motivation 3.08±0.38 vs. 3.42±0.36, bore- p ·31, and r=ー.42, p .23, respectively). Separate analy- dom 2.25士0.33 vs. 2.00±0.28, concentration 2.92± 0.38 vs ses for the three valence categories of facial expression 3.42±0.26, tension 2.25士0.31 vs. 2.08±0.29; at recognition revealed that the association between memory accuracy testing: sleepiness 1 and NonREM sleep was significant for angry and happy, ±0.31 vs. 3.58±0.23, motivation 3.67 ±0.28 vs. 3.25±0.18 but not neutral faces (angry: r=.79,p= .006, happy: r=.86, boredom 2.17±0.24 vs. 1.92±0.23, concentration 3.42± p=.001, neutral: r=.03, p=.93). The same pattern, 0.26 vs. 3.42士0.19, tension 2.08士0.34 vs. 2.00±0.30, p> although less pronounced, was found for the correlation .19, for all main effects of Sleep and Sleep× Phase interac between memory accuracy and total sleep time in the night after learning (all fac 66, p= .037, angry faces: r=.61, p=.063, neutral faces: recognition testing than at learning (sleepiness, p

Answer 1

For the first correlation:

a) The variables used in the correlation are overall memory accuracy and amount of NonREM sleep during consolidation sleep

b) Both the variables are in ratio scale (quantitative in nature and have a meaningful value of zero)

c) As the correlation coefficient is 0.79, it has moderate strength. For a correlation to be strong, r should be more than 0.8.

D) The relationship is positive as the correlation coefficient is positive.

E) The correlation is statistically significant as the p-value is 0.007 (<0.05).